INTRODUCTION — Asthma is a common lung disease affecting millions of people worldwide. It is caused by narrowing of the small airways (tubes) in the lungs. This narrowing is usually reversible, but may occasionally become permanent over time. Many different genetic and environmental factors play a role in causing asthma. Symptoms of asthma include wheezing, coughing, chest tightness, and shortness of breath. These symptoms tend to come and go, and are related to the degree of airway narrowing in the lungs.
A number of different medicines are useful in treating asthma, but not all asthma medicines are appropriate for every patient. Medicines used to treat asthma vary in cost, method of delivery, and potential side effects. Patients are affected differently by asthma, so patients, doctors, and other health care professionals must work together to develop an individualized treatment plan.
The purpose of asthma treatment is to manage the disease in order to live as normal a life as possible. This requires being well educated about the disease and being an active player in managing it. Most people with asthma are successful in controlling the disease.
The severity of asthma is an important factor in determining an asthma treatment plan. Asthma is generally classified as mild, moderate, or severe based on history of the disease, studies of lung function, and medication use. A patient's history includes frequency and severity of symptoms that occur with activities of daily living, such as walking, running, climbing stairs, carrying packages up stairs, and sleeping. The majority of people with asthma have a mild case (show table 1).
Successful management of asthma involves four components: Understanding the disease and how to treat it Controlling things that trigger asthma Regularly monitoring symptoms and lung function Medication
CONTROLLING ASTHMA TRIGGERS — The factors that set off and exacerbate asthma symptoms are called "triggers." Identifying and avoiding asthma triggers is essential in preventing asthma flare-ups. Common triggers generally fall into several categories: Allergens (including dust and animal fur) Respiratory infections Irritants (such as smoke or chemicals) Physical activity Emotional stress Menstrual cycle in women
A small number of patients will develop asthmatic symptoms after exposure to aspirin or other nonsteroidal antiinflammatory medications, like ibuprofen or naproxen. (See "Patient information: Trigger avoidance in asthma").
After identifying potential asthma triggers, a patient and their clinician should develop a plan to deal with the triggers. There are three main options: Avoid the trigger entirely (eg, if allergic to animals, do not own pets, or if asthma is triggered by dust, have someone else do the house cleaning) Limit exposure to the trigger if it cannot be completely avoided (eg, move to another seat if someone with strong perfume is seated nearby) Take an extra dose of bronchodilator medication before exposure to a trigger. Talk with a healthcare provider before using this approach; it should only be used if the first two options are not possible. Be careful not to use more than twice the amount of medication normally used.
MONITORING SYMPTOMS AND LUNG FUNCTION — Successful management of asthma relies on a patient's ability to monitor their condition regularly. This is done by recording the frequency and severity of symptoms (such as wheezing, coughing, and shortness of breath) and by obtaining numerical measurements of lung function, such as peak expiratory flow rates (PEFRs).
Peak expiratory flow rate — PEFR measures the rate at which a patient can exhale. This rate is dependent on the degree of airway narrowing. PEFR monitoring can provide firm data that can be used to make treatment decisions. The National Asthma Education and Prevention Program recommends that people with moderate to severe persistent asthma use a peak flow meter daily to monitor their lung function. PEFR measurement can be used to monitor lung function and response to treatment, assess the severity of asthma attacks, and guide decisions regarding treatment.
Peak flow meters are inexpensive and easy to use. PEFR is usually measured when getting up in the morning and before going to bed at night. For more information, see "Patient Information: How to use a peak flow meter".
Asthma diary — Using an asthma diary to record daily peak flow readings and asthma symptoms can help patients to identify a cause-and-effect relationship between exposure to certain asthma triggers, decreases in peak flow, and exacerbations of asthma. The diary can also help track medication use (show figure 1).
TREATMENT — Medication is the main form of treatment for most people in managing asthma. The medications used vary according to the type and severity of asthma. An individual's asthma treatment plan must constantly be adjusted because the severity of the disorder changes over time. As symptoms improve, medication should be reduced. As symptoms worsen, medication should be increased.
Mild intermittent asthma — People with mild intermittent asthma are defined in part as those who have: Symptoms of asthma occurring two or fewer times per week Two or fewer awakenings during the night per month Peak flow measurements when asymptomatic that are consistently within the normal range (ie, PEFR >80 percent of predicted normal)
In addition, a person with asthma that is triggered only during vigorous exercise (exercise-induced asthma) might fit into this category even if exercising more than twice per week. Others in whom asthmatic symptoms arise only under certain infrequently occurring circumstances (eg, when exposed to a cat or during some viral respiratory tract infections) are also considered to have mild intermittent asthma.
Bronchodilators — People with mild intermittent asthma have the mildest form of asthma and require treatment with bronchodilators (called beta agonists) only occasionally. Bronchodilators are medicines that help open the narrowed airways of patients with asthma. Although patients with mild intermittent asthma can take bronchodilators on a regularly scheduled basis without harmful effects, there is no advantage over taking them only when needed.
The preferred way of taking medication for people with mild intermittent asthma is using an inhaler. This method allows the medication to take effect rapidly with maximum strength and minimal side effects. People who can predict triggers of asthma symptoms (eg, exercise-induced symptoms) are encouraged to use their inhalers approximately 10 minutes before exposure in order to prevent symptoms from occurring. Inhaled beta agonists can also relieve symptoms after they have started. (See "Patient Information: Metered dose inhaler techniques" for information on how to use an inhaler).
Some people experience tremulousness, palpitations, and/or anxiety from inhaled beta agonists. Using a single inhalation of the medication for prevention or relief of symptoms rather than the usual two puffs may alleviate these reactions with a minimal decrease in benefit.
Mast cell stabilizers — Mast cell stabilizing medications, such as cromolyn (Intal®) and nedocromil (Tilade®), are alternate medications for prevention of exercise-induced symptoms. Two inhalations of either medication taken about 10 to 20 minutes before exercising can provide effective preventive treatment with no side effects. However, they cannot relieve symptoms that have already started. These medications provide additive protection when used with a beta agonist before exercising.
Mild persistent asthma — People with mild persistent asthma have symptoms regularly but not every day. Although they have days with some limitation in their activities, they are typically not restricted. They may be awakened from sleep three to four times a month by symptoms but most nights they sleep well. Lung function is usually normal between episodes but becomes abnormal during an asthma attack.
It is useful to start regular treatment with antiinflammatory medications when a person has one of the following: Symptoms requiring relief with an inhaled bronchodilator more than twice a week Awakenings during the night more often than twice a month Changes in PEFR of more than 20 percent
Antiinflammatory medications — Regular treatment with antiinflammatory medications reduces the frequency of symptoms (and the need for inhaled bronchodilators for symptom relief), improves quality of life, and decreases the risk of serious exacerbations. By reducing over-responsiveness of the bronchial tubes, regular antiinflammatory treatment change the basic condition of the airways that causes asthma and reduces a patient's exaggerated sensitivity to asthma triggers.
For adults, the most frequently recommended type of antiinflammatory medication is an inhaled corticosteroid. It is usually taken twice a day. People who are taking antiinflammatory medication regularly should continue to use their inhaled bronchodilator as needed for relief of symptoms and before exposure to their asthma triggers. Side effects — The most common side effect from this type of medication is oral candidiasis (thrush). This complication is infrequent when inhaled corticosteroids are taken with a spacer (which helps to deliver medication to the lungs rather than the mouth) and if the patient rinses their mouth immediately after inhalation.
Hoarse voice and sore throat (without thrush) are less common side effects that usually resolve quickly after temporarily stopping the medication. If inhalation causes coughing with each use, changing to a different steroid preparation may relieve the problem.
Leukotriene blockers — A separate category of medications called leukotriene blockers provides an alternative to inhaled steroids in patients with mild persistent asthma. They are in pill form, are taken by mouth once or twice daily, and have very few side effects. However, compared to inhaled corticosteroids they are somewhat less effective in controlling asthma and are more expensive.
Moderate persistent asthma — The presence of any of the following is an indication of moderate asthma: Daily symptoms Daily need for bronchodilator medications Asthma attacks that interfere with daily activities Awakening during the night more than once per week PEFR 60 to 80 percent of normal
Controller medications — Patients who have moderate persistent asthma often need to use medicines on a daily basis to keep their asthma under control. For these patients, controller medicines are important, and should be used regularly even if there are no symptoms of active asthma. Controller medicines work over time to decrease the amount of inflammation (or narrowing) of the small airways. Some controller medicines are delivered by inhaler while others are taken by mouth. Controller medicines include long-acting bronchodilators, inhaled or oral steroids, and oral leukotriene modifiers like montelukast (Singulair®)
Many people whose asthma is poorly controlled on low doses of inhaled corticosteroids improve when the dose is raised. If they have moderate persistent asthma, they should use a dose at the high end of the medium dose range. They should also use quick-acting beta agonists for relief of sudden onset symptoms.
If symptoms continue several weeks after starting inhaled corticosteroids at the high end of the medium dose range, a second controller medication should be added. These include salmeterol (contained in Advair®), montelukast (Singulair®) zafirlukast (Accolate®) or sustained release theophylline. Side effects — As the dose of inhaled corticosteroids is increased, the likelihood of systemic absorption and the chance for significant side effects from long-term use increase. Side effects from long-term use may include: Increased pressure in the eye Cataracts Growth retardation Increased bone loss
The risk of these complications is far less with inhaled corticosteroids than with oral corticosteroids. Nevertheless, in patients with moderate or severe asthma whose disease has been well controlled with high-dose inhaled corticosteroids, every effort should be made to reduce the dose to as low as possible while maintaining good asthma control and minimizing the risk of exacerbations.
Severe asthma — The following are indications of severe chronic asthma: Frequent asthma exacerbations as a result of minor exposures to viral illnesses, allergens, exercise, or air pollutants Awakenings from sleep four to seven nights per week PEFR below 60 percent of predicted normal Inability to achieve normal lung function despite chronic treatment with multiple medications, including inhaled steroids at moderate to high dose, or continuous, every other day, or multiple short courses of oral steroids.
People with severe asthma usually require multiple controller medications and bronchodilator medications on a regular basis. If they cannot achieve symptom control with two controller medications, they are likely to require the addition of oral corticosteroids or high-dose inhaled corticosteroids. Consultation with an asthma specialist is warranted in cases of severe asthma.
ASTHMA IN PREGNANCY — Asthma is the most common condition that affects the lungs during pregnancy. About 4 percent of pregnant women have asthma. With good asthma treatment during pregnancy, most women can breathe easily, have a normal pregnancy, and give birth to a healthy baby.
Before becoming pregnant, women with asthma should learn as much as they can about the condition and talk with their doctors about asthma treatment during pregnancy. More information about asthma during pregnancy is presented separately. (See "Patient Information: Pregnancy and asthma").
WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two patients are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.
This discussion will be updated as needed every four months on our web site (www.patients.uptodate.com). Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information.
A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable. The National Library of Medicine
(www.nlm.nih.gov/medlineplus/healthtopics.html)
National Heart, Lung, and Blood Institute
(www.nhlbi.nih.gov/)
American Lung Association
(www.lungusa.org)
What's Asthma All About?
(www.whatsasthma.org)
The Asthma and Allergy Foundation of America
(www.aafa.org)
American Academy of Allergy, Asthma, and Immunology
(www.aaaai.org/patients.stm)
American College of Allergy, Asthma, and Immunology
(www.acaai.org/public/)
[1-3]
Use of UpToDate is subject to the Subscription and License Agreement. REFERENCES 1. Worldwide variation in prevalence of symptoms of asthma, allergic rhinoconjunctivitis, and atopic eczema: ISAAC. The International Study of Asthma and Allergies in Childhood (ISAAC) Steering Committee. Lancet 1998; 351:1225.
2. National Asthma Education Program Expert Panel. Guidelines for the diagnosis and management of asthma. US Department of Health and Human Services, National Institutes of Health, Bethesda, 1997.
3. National Asthma Education and Prevention Program Expert Panel Executive Summary Report: Guidelines for the Diagnosis and Management of Asthma - Update on Selected Topics 2002. National Institutes of Health, National Heart, Lung, and Blood Institute, Publication No. 02-5075, 2002. Full text available online: www.nhlbi.nih.gov/guidelines/asthma/asthgdln.pdf (Accessed 3/7/05).
Tuesday, October 9, 2007
ASTHMA Patient information: Overview of managing asthma
INTRODUCTION — Asthma is a common lung disease affecting millions of people worldwide. It is caused by narrowing of the small airways (tubes) in the lungs. This narrowing is usually reversible, but may occasionally become permanent over time. Many different genetic and environmental factors play a role in causing asthma. Symptoms of asthma include wheezing, coughing, chest tightness, and shortness of breath. These symptoms tend to come and go, and are related to the degree of airway narrowing in the lungs.
A number of different medicines are useful in treating asthma, but not all asthma medicines are appropriate for every patient. Medicines used to treat asthma vary in cost, method of delivery, and potential side effects. Patients are affected differently by asthma, so patients, doctors, and other health care professionals must work together to develop an individualized treatment plan.
The purpose of asthma treatment is to manage the disease in order to live as normal a life as possible. This requires being well educated about the disease and being an active player in managing it. Most people with asthma are successful in controlling the disease.
The severity of asthma is an important factor in determining an asthma treatment plan. Asthma is generally classified as mild, moderate, or severe based on history of the disease, studies of lung function, and medication use. A patient's history includes frequency and severity of symptoms that occur with activities of daily living, such as walking, running, climbing stairs, carrying packages up stairs, and sleeping. The majority of people with asthma have a mild case (show table 1).
Successful management of asthma involves four components: Understanding the disease and how to treat it Controlling things that trigger asthma Regularly monitoring symptoms and lung function Medication
CONTROLLING ASTHMA TRIGGERS — The factors that set off and exacerbate asthma symptoms are called "triggers." Identifying and avoiding asthma triggers is essential in preventing asthma flare-ups. Common triggers generally fall into several categories: Allergens (including dust and animal fur) Respiratory infections Irritants (such as smoke or chemicals) Physical activity Emotional stress Menstrual cycle in women
A small number of patients will develop asthmatic symptoms after exposure to aspirin or other nonsteroidal antiinflammatory medications, like ibuprofen or naproxen. (See "Patient information: Trigger avoidance in asthma").
After identifying potential asthma triggers, a patient and their clinician should develop a plan to deal with the triggers. There are three main options: Avoid the trigger entirely (eg, if allergic to animals, do not own pets, or if asthma is triggered by dust, have someone else do the house cleaning) Limit exposure to the trigger if it cannot be completely avoided (eg, move to another seat if someone with strong perfume is seated nearby) Take an extra dose of bronchodilator medication before exposure to a trigger. Talk with a healthcare provider before using this approach; it should only be used if the first two options are not possible. Be careful not to use more than twice the amount of medication normally used.
MONITORING SYMPTOMS AND LUNG FUNCTION — Successful management of asthma relies on a patient's ability to monitor their condition regularly. This is done by recording the frequency and severity of symptoms (such as wheezing, coughing, and shortness of breath) and by obtaining numerical measurements of lung function, such as peak expiratory flow rates (PEFRs).
Peak expiratory flow rate — PEFR measures the rate at which a patient can exhale. This rate is dependent on the degree of airway narrowing. PEFR monitoring can provide firm data that can be used to make treatment decisions. The National Asthma Education and Prevention Program recommends that people with moderate to severe persistent asthma use a peak flow meter daily to monitor their lung function. PEFR measurement can be used to monitor lung function and response to treatment, assess the severity of asthma attacks, and guide decisions regarding treatment.
Peak flow meters are inexpensive and easy to use. PEFR is usually measured when getting up in the morning and before going to bed at night. For more information, see "Patient Information: How to use a peak flow meter".
Asthma diary — Using an asthma diary to record daily peak flow readings and asthma symptoms can help patients to identify a cause-and-effect relationship between exposure to certain asthma triggers, decreases in peak flow, and exacerbations of asthma. The diary can also help track medication use (show figure 1).
TREATMENT — Medication is the main form of treatment for most people in managing asthma. The medications used vary according to the type and severity of asthma. An individual's asthma treatment plan must constantly be adjusted because the severity of the disorder changes over time. As symptoms improve, medication should be reduced. As symptoms worsen, medication should be increased.
Mild intermittent asthma — People with mild intermittent asthma are defined in part as those who have: Symptoms of asthma occurring two or fewer times per week Two or fewer awakenings during the night per month Peak flow measurements when asymptomatic that are consistently within the normal range (ie, PEFR >80 percent of predicted normal)
In addition, a person with asthma that is triggered only during vigorous exercise (exercise-induced asthma) might fit into this category even if exercising more than twice per week. Others in whom asthmatic symptoms arise only under certain infrequently occurring circumstances (eg, when exposed to a cat or during some viral respiratory tract infections) are also considered to have mild intermittent asthma.
Bronchodilators — People with mild intermittent asthma have the mildest form of asthma and require treatment with bronchodilators (called beta agonists) only occasionally. Bronchodilators are medicines that help open the narrowed airways of patients with asthma. Although patients with mild intermittent asthma can take bronchodilators on a regularly scheduled basis without harmful effects, there is no advantage over taking them only when needed.
The preferred way of taking medication for people with mild intermittent asthma is using an inhaler. This method allows the medication to take effect rapidly with maximum strength and minimal side effects. People who can predict triggers of asthma symptoms (eg, exercise-induced symptoms) are encouraged to use their inhalers approximately 10 minutes before exposure in order to prevent symptoms from occurring. Inhaled beta agonists can also relieve symptoms after they have started. (See "Patient Information: Metered dose inhaler techniques" for information on how to use an inhaler).
Some people experience tremulousness, palpitations, and/or anxiety from inhaled beta agonists. Using a single inhalation of the medication for prevention or relief of symptoms rather than the usual two puffs may alleviate these reactions with a minimal decrease in benefit.
Mast cell stabilizers — Mast cell stabilizing medications, such as cromolyn (Intal®) and nedocromil (Tilade®), are alternate medications for prevention of exercise-induced symptoms. Two inhalations of either medication taken about 10 to 20 minutes before exercising can provide effective preventive treatment with no side effects. However, they cannot relieve symptoms that have already started. These medications provide additive protection when used with a beta agonist before exercising.
Mild persistent asthma — People with mild persistent asthma have symptoms regularly but not every day. Although they have days with some limitation in their activities, they are typically not restricted. They may be awakened from sleep three to four times a month by symptoms but most nights they sleep well. Lung function is usually normal between episodes but becomes abnormal during an asthma attack.
It is useful to start regular treatment with antiinflammatory medications when a person has one of the following: Symptoms requiring relief with an inhaled bronchodilator more than twice a week Awakenings during the night more often than twice a month Changes in PEFR of more than 20 percent
Antiinflammatory medications — Regular treatment with antiinflammatory medications reduces the frequency of symptoms (and the need for inhaled bronchodilators for symptom relief), improves quality of life, and decreases the risk of serious exacerbations. By reducing over-responsiveness of the bronchial tubes, regular antiinflammatory treatment change the basic condition of the airways that causes asthma and reduces a patient's exaggerated sensitivity to asthma triggers.
For adults, the most frequently recommended type of antiinflammatory medication is an inhaled corticosteroid. It is usually taken twice a day. People who are taking antiinflammatory medication regularly should continue to use their inhaled bronchodilator as needed for relief of symptoms and before exposure to their asthma triggers. Side effects — The most common side effect from this type of medication is oral candidiasis (thrush). This complication is infrequent when inhaled corticosteroids are taken with a spacer (which helps to deliver medication to the lungs rather than the mouth) and if the patient rinses their mouth immediately after inhalation.
Hoarse voice and sore throat (without thrush) are less common side effects that usually resolve quickly after temporarily stopping the medication. If inhalation causes coughing with each use, changing to a different steroid preparation may relieve the problem.
Leukotriene blockers — A separate category of medications called leukotriene blockers provides an alternative to inhaled steroids in patients with mild persistent asthma. They are in pill form, are taken by mouth once or twice daily, and have very few side effects. However, compared to inhaled corticosteroids they are somewhat less effective in controlling asthma and are more expensive.
Moderate persistent asthma — The presence of any of the following is an indication of moderate asthma: Daily symptoms Daily need for bronchodilator medications Asthma attacks that interfere with daily activities Awakening during the night more than once per week PEFR 60 to 80 percent of normal
Controller medications — Patients who have moderate persistent asthma often need to use medicines on a daily basis to keep their asthma under control. For these patients, controller medicines are important, and should be used regularly even if there are no symptoms of active asthma. Controller medicines work over time to decrease the amount of inflammation (or narrowing) of the small airways. Some controller medicines are delivered by inhaler while others are taken by mouth. Controller medicines include long-acting bronchodilators, inhaled or oral steroids, and oral leukotriene modifiers like montelukast (Singulair®)
Many people whose asthma is poorly controlled on low doses of inhaled corticosteroids improve when the dose is raised. If they have moderate persistent asthma, they should use a dose at the high end of the medium dose range. They should also use quick-acting beta agonists for relief of sudden onset symptoms.
If symptoms continue several weeks after starting inhaled corticosteroids at the high end of the medium dose range, a second controller medication should be added. These include salmeterol (contained in Advair®), montelukast (Singulair®) zafirlukast (Accolate®) or sustained release theophylline. Side effects — As the dose of inhaled corticosteroids is increased, the likelihood of systemic absorption and the chance for significant side effects from long-term use increase. Side effects from long-term use may include: Increased pressure in the eye Cataracts Growth retardation Increased bone loss
The risk of these complications is far less with inhaled corticosteroids than with oral corticosteroids. Nevertheless, in patients with moderate or severe asthma whose disease has been well controlled with high-dose inhaled corticosteroids, every effort should be made to reduce the dose to as low as possible while maintaining good asthma control and minimizing the risk of exacerbations.
Severe asthma — The following are indications of severe chronic asthma: Frequent asthma exacerbations as a result of minor exposures to viral illnesses, allergens, exercise, or air pollutants Awakenings from sleep four to seven nights per week PEFR below 60 percent of predicted normal Inability to achieve normal lung function despite chronic treatment with multiple medications, including inhaled steroids at moderate to high dose, or continuous, every other day, or multiple short courses of oral steroids.
People with severe asthma usually require multiple controller medications and bronchodilator medications on a regular basis. If they cannot achieve symptom control with two controller medications, they are likely to require the addition of oral corticosteroids or high-dose inhaled corticosteroids. Consultation with an asthma specialist is warranted in cases of severe asthma.
ASTHMA IN PREGNANCY — Asthma is the most common condition that affects the lungs during pregnancy. About 4 percent of pregnant women have asthma. With good asthma treatment during pregnancy, most women can breathe easily, have a normal pregnancy, and give birth to a healthy baby.
Before becoming pregnant, women with asthma should learn as much as they can about the condition and talk with their doctors about asthma treatment during pregnancy. More information about asthma during pregnancy is presented separately. (See "Patient Information: Pregnancy and asthma").
WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two patients are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.
This discussion will be updated as needed every four months on our web site (www.patients.uptodate.com). Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information.
A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable. The National Library of Medicine
(www.nlm.nih.gov/medlineplus/healthtopics.html)
National Heart, Lung, and Blood Institute
(www.nhlbi.nih.gov/)
American Lung Association
(www.lungusa.org)
What's Asthma All About?
(www.whatsasthma.org)
The Asthma and Allergy Foundation of America
(www.aafa.org)
American Academy of Allergy, Asthma, and Immunology
(www.aaaai.org/patients.stm)
American College of Allergy, Asthma, and Immunology
(www.acaai.org/public/)
[1-3]
Use of UpToDate is subject to the Subscription and License Agreement. REFERENCES 1. Worldwide variation in prevalence of symptoms of asthma, allergic rhinoconjunctivitis, and atopic eczema: ISAAC. The International Study of Asthma and Allergies in Childhood (ISAAC) Steering Committee. Lancet 1998; 351:1225.
2. National Asthma Education Program Expert Panel. Guidelines for the diagnosis and management of asthma. US Department of Health and Human Services, National Institutes of Health, Bethesda, 1997.
3. National Asthma Education and Prevention Program Expert Panel Executive Summary Report: Guidelines for the Diagnosis and Management of Asthma - Update on Selected Topics 2002. National Institutes of Health, National Heart, Lung, and Blood Institute, Publication No. 02-5075, 2002. Full text available online: www.nhlbi.nih.gov/guidelines/asthma/asthgdln.pdf (Accessed 3/7/05).
A number of different medicines are useful in treating asthma, but not all asthma medicines are appropriate for every patient. Medicines used to treat asthma vary in cost, method of delivery, and potential side effects. Patients are affected differently by asthma, so patients, doctors, and other health care professionals must work together to develop an individualized treatment plan.
The purpose of asthma treatment is to manage the disease in order to live as normal a life as possible. This requires being well educated about the disease and being an active player in managing it. Most people with asthma are successful in controlling the disease.
The severity of asthma is an important factor in determining an asthma treatment plan. Asthma is generally classified as mild, moderate, or severe based on history of the disease, studies of lung function, and medication use. A patient's history includes frequency and severity of symptoms that occur with activities of daily living, such as walking, running, climbing stairs, carrying packages up stairs, and sleeping. The majority of people with asthma have a mild case (show table 1).
Successful management of asthma involves four components: Understanding the disease and how to treat it Controlling things that trigger asthma Regularly monitoring symptoms and lung function Medication
CONTROLLING ASTHMA TRIGGERS — The factors that set off and exacerbate asthma symptoms are called "triggers." Identifying and avoiding asthma triggers is essential in preventing asthma flare-ups. Common triggers generally fall into several categories: Allergens (including dust and animal fur) Respiratory infections Irritants (such as smoke or chemicals) Physical activity Emotional stress Menstrual cycle in women
A small number of patients will develop asthmatic symptoms after exposure to aspirin or other nonsteroidal antiinflammatory medications, like ibuprofen or naproxen. (See "Patient information: Trigger avoidance in asthma").
After identifying potential asthma triggers, a patient and their clinician should develop a plan to deal with the triggers. There are three main options: Avoid the trigger entirely (eg, if allergic to animals, do not own pets, or if asthma is triggered by dust, have someone else do the house cleaning) Limit exposure to the trigger if it cannot be completely avoided (eg, move to another seat if someone with strong perfume is seated nearby) Take an extra dose of bronchodilator medication before exposure to a trigger. Talk with a healthcare provider before using this approach; it should only be used if the first two options are not possible. Be careful not to use more than twice the amount of medication normally used.
MONITORING SYMPTOMS AND LUNG FUNCTION — Successful management of asthma relies on a patient's ability to monitor their condition regularly. This is done by recording the frequency and severity of symptoms (such as wheezing, coughing, and shortness of breath) and by obtaining numerical measurements of lung function, such as peak expiratory flow rates (PEFRs).
Peak expiratory flow rate — PEFR measures the rate at which a patient can exhale. This rate is dependent on the degree of airway narrowing. PEFR monitoring can provide firm data that can be used to make treatment decisions. The National Asthma Education and Prevention Program recommends that people with moderate to severe persistent asthma use a peak flow meter daily to monitor their lung function. PEFR measurement can be used to monitor lung function and response to treatment, assess the severity of asthma attacks, and guide decisions regarding treatment.
Peak flow meters are inexpensive and easy to use. PEFR is usually measured when getting up in the morning and before going to bed at night. For more information, see "Patient Information: How to use a peak flow meter".
Asthma diary — Using an asthma diary to record daily peak flow readings and asthma symptoms can help patients to identify a cause-and-effect relationship between exposure to certain asthma triggers, decreases in peak flow, and exacerbations of asthma. The diary can also help track medication use (show figure 1).
TREATMENT — Medication is the main form of treatment for most people in managing asthma. The medications used vary according to the type and severity of asthma. An individual's asthma treatment plan must constantly be adjusted because the severity of the disorder changes over time. As symptoms improve, medication should be reduced. As symptoms worsen, medication should be increased.
Mild intermittent asthma — People with mild intermittent asthma are defined in part as those who have: Symptoms of asthma occurring two or fewer times per week Two or fewer awakenings during the night per month Peak flow measurements when asymptomatic that are consistently within the normal range (ie, PEFR >80 percent of predicted normal)
In addition, a person with asthma that is triggered only during vigorous exercise (exercise-induced asthma) might fit into this category even if exercising more than twice per week. Others in whom asthmatic symptoms arise only under certain infrequently occurring circumstances (eg, when exposed to a cat or during some viral respiratory tract infections) are also considered to have mild intermittent asthma.
Bronchodilators — People with mild intermittent asthma have the mildest form of asthma and require treatment with bronchodilators (called beta agonists) only occasionally. Bronchodilators are medicines that help open the narrowed airways of patients with asthma. Although patients with mild intermittent asthma can take bronchodilators on a regularly scheduled basis without harmful effects, there is no advantage over taking them only when needed.
The preferred way of taking medication for people with mild intermittent asthma is using an inhaler. This method allows the medication to take effect rapidly with maximum strength and minimal side effects. People who can predict triggers of asthma symptoms (eg, exercise-induced symptoms) are encouraged to use their inhalers approximately 10 minutes before exposure in order to prevent symptoms from occurring. Inhaled beta agonists can also relieve symptoms after they have started. (See "Patient Information: Metered dose inhaler techniques" for information on how to use an inhaler).
Some people experience tremulousness, palpitations, and/or anxiety from inhaled beta agonists. Using a single inhalation of the medication for prevention or relief of symptoms rather than the usual two puffs may alleviate these reactions with a minimal decrease in benefit.
Mast cell stabilizers — Mast cell stabilizing medications, such as cromolyn (Intal®) and nedocromil (Tilade®), are alternate medications for prevention of exercise-induced symptoms. Two inhalations of either medication taken about 10 to 20 minutes before exercising can provide effective preventive treatment with no side effects. However, they cannot relieve symptoms that have already started. These medications provide additive protection when used with a beta agonist before exercising.
Mild persistent asthma — People with mild persistent asthma have symptoms regularly but not every day. Although they have days with some limitation in their activities, they are typically not restricted. They may be awakened from sleep three to four times a month by symptoms but most nights they sleep well. Lung function is usually normal between episodes but becomes abnormal during an asthma attack.
It is useful to start regular treatment with antiinflammatory medications when a person has one of the following: Symptoms requiring relief with an inhaled bronchodilator more than twice a week Awakenings during the night more often than twice a month Changes in PEFR of more than 20 percent
Antiinflammatory medications — Regular treatment with antiinflammatory medications reduces the frequency of symptoms (and the need for inhaled bronchodilators for symptom relief), improves quality of life, and decreases the risk of serious exacerbations. By reducing over-responsiveness of the bronchial tubes, regular antiinflammatory treatment change the basic condition of the airways that causes asthma and reduces a patient's exaggerated sensitivity to asthma triggers.
For adults, the most frequently recommended type of antiinflammatory medication is an inhaled corticosteroid. It is usually taken twice a day. People who are taking antiinflammatory medication regularly should continue to use their inhaled bronchodilator as needed for relief of symptoms and before exposure to their asthma triggers. Side effects — The most common side effect from this type of medication is oral candidiasis (thrush). This complication is infrequent when inhaled corticosteroids are taken with a spacer (which helps to deliver medication to the lungs rather than the mouth) and if the patient rinses their mouth immediately after inhalation.
Hoarse voice and sore throat (without thrush) are less common side effects that usually resolve quickly after temporarily stopping the medication. If inhalation causes coughing with each use, changing to a different steroid preparation may relieve the problem.
Leukotriene blockers — A separate category of medications called leukotriene blockers provides an alternative to inhaled steroids in patients with mild persistent asthma. They are in pill form, are taken by mouth once or twice daily, and have very few side effects. However, compared to inhaled corticosteroids they are somewhat less effective in controlling asthma and are more expensive.
Moderate persistent asthma — The presence of any of the following is an indication of moderate asthma: Daily symptoms Daily need for bronchodilator medications Asthma attacks that interfere with daily activities Awakening during the night more than once per week PEFR 60 to 80 percent of normal
Controller medications — Patients who have moderate persistent asthma often need to use medicines on a daily basis to keep their asthma under control. For these patients, controller medicines are important, and should be used regularly even if there are no symptoms of active asthma. Controller medicines work over time to decrease the amount of inflammation (or narrowing) of the small airways. Some controller medicines are delivered by inhaler while others are taken by mouth. Controller medicines include long-acting bronchodilators, inhaled or oral steroids, and oral leukotriene modifiers like montelukast (Singulair®)
Many people whose asthma is poorly controlled on low doses of inhaled corticosteroids improve when the dose is raised. If they have moderate persistent asthma, they should use a dose at the high end of the medium dose range. They should also use quick-acting beta agonists for relief of sudden onset symptoms.
If symptoms continue several weeks after starting inhaled corticosteroids at the high end of the medium dose range, a second controller medication should be added. These include salmeterol (contained in Advair®), montelukast (Singulair®) zafirlukast (Accolate®) or sustained release theophylline. Side effects — As the dose of inhaled corticosteroids is increased, the likelihood of systemic absorption and the chance for significant side effects from long-term use increase. Side effects from long-term use may include: Increased pressure in the eye Cataracts Growth retardation Increased bone loss
The risk of these complications is far less with inhaled corticosteroids than with oral corticosteroids. Nevertheless, in patients with moderate or severe asthma whose disease has been well controlled with high-dose inhaled corticosteroids, every effort should be made to reduce the dose to as low as possible while maintaining good asthma control and minimizing the risk of exacerbations.
Severe asthma — The following are indications of severe chronic asthma: Frequent asthma exacerbations as a result of minor exposures to viral illnesses, allergens, exercise, or air pollutants Awakenings from sleep four to seven nights per week PEFR below 60 percent of predicted normal Inability to achieve normal lung function despite chronic treatment with multiple medications, including inhaled steroids at moderate to high dose, or continuous, every other day, or multiple short courses of oral steroids.
People with severe asthma usually require multiple controller medications and bronchodilator medications on a regular basis. If they cannot achieve symptom control with two controller medications, they are likely to require the addition of oral corticosteroids or high-dose inhaled corticosteroids. Consultation with an asthma specialist is warranted in cases of severe asthma.
ASTHMA IN PREGNANCY — Asthma is the most common condition that affects the lungs during pregnancy. About 4 percent of pregnant women have asthma. With good asthma treatment during pregnancy, most women can breathe easily, have a normal pregnancy, and give birth to a healthy baby.
Before becoming pregnant, women with asthma should learn as much as they can about the condition and talk with their doctors about asthma treatment during pregnancy. More information about asthma during pregnancy is presented separately. (See "Patient Information: Pregnancy and asthma").
WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two patients are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.
This discussion will be updated as needed every four months on our web site (www.patients.uptodate.com). Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information.
A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable. The National Library of Medicine
(www.nlm.nih.gov/medlineplus/healthtopics.html)
National Heart, Lung, and Blood Institute
(www.nhlbi.nih.gov/)
American Lung Association
(www.lungusa.org)
What's Asthma All About?
(www.whatsasthma.org)
The Asthma and Allergy Foundation of America
(www.aafa.org)
American Academy of Allergy, Asthma, and Immunology
(www.aaaai.org/patients.stm)
American College of Allergy, Asthma, and Immunology
(www.acaai.org/public/)
[1-3]
Use of UpToDate is subject to the Subscription and License Agreement. REFERENCES 1. Worldwide variation in prevalence of symptoms of asthma, allergic rhinoconjunctivitis, and atopic eczema: ISAAC. The International Study of Asthma and Allergies in Childhood (ISAAC) Steering Committee. Lancet 1998; 351:1225.
2. National Asthma Education Program Expert Panel. Guidelines for the diagnosis and management of asthma. US Department of Health and Human Services, National Institutes of Health, Bethesda, 1997.
3. National Asthma Education and Prevention Program Expert Panel Executive Summary Report: Guidelines for the Diagnosis and Management of Asthma - Update on Selected Topics 2002. National Institutes of Health, National Heart, Lung, and Blood Institute, Publication No. 02-5075, 2002. Full text available online: www.nhlbi.nih.gov/guidelines/asthma/asthgdln.pdf (Accessed 3/7/05).
Asthma Patient information: Metered dose inhaler techniques
INTRODUCTION — Inhaled medications are the cornerstone of asthma therapy, but they can only be effective if they are used properly. Correct technique delivers the medication more effectively and leads to better airway responses.The result of poor technique is that little or no medicine reaches the lungs.
Unfortunately, many people with asthma do not use the best inhaler technique. However, studies have shown that almost everyone can learn proper inhaler technique with adequate training and practice.
METERED DOSE INHALERS — Metered dose inhalers (MDIs) are used to deliver a variety of inhaled medications, including quick relief bronchodilators such as Proventil®, Ventolin®, or Alupent®, and controller medicines such as corticosteroids (Flovent®, QVAR®, Pulmicort®, and others) and cromolyn (Intal®). Medications are delivered by pushing down on a canister to release a specific amount of aerosolized medication. An MDI consists of a pressurized canister, a metering valve and stem, and a mouthpiece actuator (show figure 1).
The canister contains the drug suspended in a mixture of propellants, surfactants, preservatives, flavoring agents, and dispersal agents. The propellant has traditionally been a chlorofluorocarbon (CFC). Since the development of an international agreement to ban CFCs, new CFC-free propellants have become available, which use hydrofluoroalkane (HFA) instead of CFCs. Patients who previously used CFC devices should be aware that HFA devices may have a different feel or taste compared to their old device. However, this does not mean the medicine is not reaching their lungs.
COMMON INHALER MISTAKES — Only a portion of the medicine sprayed out of any MDI successfully reaches the lungs, even when used properly. Three common problems can further decrease the efficiency of the device and the delivery of inhaled medications: The medication is sprayed out faster than the patient can breathe it in. The patient inhales before finishing the spray of medication. The patient inhales after the medication is sprayed.
Other common mistakes include inhaling through the nose instead of the mouth, squeezing the canister twice but only inhaling once, and forgetting to take the cap off the mouthpiece.
With inhaled corticosteroids, poor technique may also increase the risk of hoarseness and fungal infection (thrush). For this reason, patients are advised to rinse their mouth with water or brush their teeth and tongue after using inhaled steroids.
For people who have persistent difficulty timing their breath with spraying the medication, there are MDIs available that automatically release the medication when the person breathes in (ie, Maxair Autohaler®).
Another alternative patients may discuss with their healthcare provider is the use of dry powder inhalers (DPIs). DPIs eliminate the need to coordinate inhalation and hand movement. DPIs deliver a fine powder to the lungs when the patient breathes in (show figure 3). Patients who use dry powdered inhalers need to inhale more forcefully than is necessary with a traditional aerosol inhaler. Thus, DPIs may not be suitable for the elderly or persons with nerve or muscle weakness. Also, patients must take care not to blow (exhale) directly into the device before breathing in, as this can scatter the medicine before it can be inhaled.
SPACER DEVICES — Medication delivery can be improved by adding a spacer device to the inhaler. A spacer holds the medicine in a chamber after it has been released from the canister, allowing the patient to inhale slowly and deeply once or twice (show figure 2). Spacers can dramatically decrease the amount of medicine deposited in the back of the mouth or on the tongue, allowing much more of the medicine to reach the lungs.
There are many spacers on the market, although little is known about the benefit of one type versus another. In general, larger sized spacers appear to be more effective than smaller ones. Proper technique and frequent cleaning are important to ensure optimal drug delivery. The package insert that comes with the spacer should be read carefully for specific directions about cleaning and use.
Cleaning the spacer — Although the powder residue that is deposited in the chamber is not harmful, it is recommended that the spacer be cleaned periodically. The spacer should be washed with warm water and dishwashing detergent; washing with water alone causes an electrostatic charge to develop, reducing the effectiveness of the spacer.
TECHNIQUE — When using a metered dose inhaler (with or without a spacer): Shake the inhaler for five seconds If using a spacer, place the mouthpiece of the inhaler into the small end of the spacer Position the inhaler with the index finger on the top of the medication canister and the thumb supporting the bottom of the inhaler Place the spacer tube or mouthpiece between the lips Close mouth around spacer or mouthpiece (show figure 4). For spacers that have a mask, hold the mask snugly to the face Exhale normally (not forcefully) Press down the top of the medication canister with the index finger to release the medication At the same time as the canister is pressed, inhale deeply and slowly until the lungs are completely filled; this should take four to six seconds Hold the medication in the lungs for 4 to 10 seconds before exhaling Wait a minimum of 15 seconds before repeating these steps for a second puff Rinse the mouth after using an inhaled steroid, and spit the water out rather than swallowing it
ASTHMA ATTACK CARE AND PREVENTION — Patients with asthma should work with their healthcare provider to ensure that their medication regimen is successful for both treating and preventing asthma attacks. Depending upon the severity of a patient's asthma, the treatment plan may include regular visits with the provider, use of one or more medications, avoiding asthma triggers, and/or home peak flow monitoring. At each visit, patients should demonstrate how they use an inhaler to their healthcare provider to ensure that the correct technique is used. (See "Patient information: Overview of managing asthma" and see "Patient information: How to use a peak flow meter" and see "Patient information: Trigger avoidance in asthma").
Ensuring medication is available — Patients should always have an adequate supply of their medication(s). This includes verifying that medication is not expired and that a spare MDI is available.
Determining when an inhaler is empty — It is not always possible to determine when an MDI canister is empty by shaking it, because some propellant remains in the canister after all of the medication has been used. A few MDIs are now being manufactured with integrated dose counters, including Ventolin-HFA®, available in the United States since June 2006. In the absence of a counter, patients may maintain a log of the number of sprays used. The MDI should be disposed of when the designated number of sprays has been reached, even if it is still possible to continue spraying. In the past, patients have been instructed to drop the canister into a bowl of water and observe how it floats. However, studies have determined that this method is not reliable and it is no longer recommended.
WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two patients are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.
This discussion will be updated as needed every four months on our web site (www.patients.uptodate.com). Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information.
A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable. National Library of Medicine
(www.nlm.nih.gov/medlineplus/healthtopics.html)
National Heart, Lung, and Blood Institute
(www.nhlbi.nih.gov/)
National Lung Health Education Program
(www.nlhep.org)
American Lung Association
(www.lungusa.org)
American Academy of Allergy, Asthma, and Immunology
(www.aaaai.org/patients.stm)
American College of Allergy, Asthma, and Immunology
(www.acaai.org/public/)
[1-3]
Use of UpToDate is subject to the Subscription and License Agreement. REFERENCES 1. Schecker, MH, Wilson, AF, Mukai, DS, et al. A device for overcoming discoordination with metered-dose inhalers. J Allergy Clin Immunol 1993; 92:783.
2. Toogood, JH. Helping your patients make better use of MDIs and spacers. J Respir Dis 1994; 15:151.
3. Melani, AS, Zanchetta, D, Barbato, N, et al. Inhalation technique and variables associated with misuse of conventional metered-dose inhalers and newer dry powder inhalers in experienced adults. Ann Allergy Asthma Immunol 2004; 93:439.
Unfortunately, many people with asthma do not use the best inhaler technique. However, studies have shown that almost everyone can learn proper inhaler technique with adequate training and practice.
METERED DOSE INHALERS — Metered dose inhalers (MDIs) are used to deliver a variety of inhaled medications, including quick relief bronchodilators such as Proventil®, Ventolin®, or Alupent®, and controller medicines such as corticosteroids (Flovent®, QVAR®, Pulmicort®, and others) and cromolyn (Intal®). Medications are delivered by pushing down on a canister to release a specific amount of aerosolized medication. An MDI consists of a pressurized canister, a metering valve and stem, and a mouthpiece actuator (show figure 1).
The canister contains the drug suspended in a mixture of propellants, surfactants, preservatives, flavoring agents, and dispersal agents. The propellant has traditionally been a chlorofluorocarbon (CFC). Since the development of an international agreement to ban CFCs, new CFC-free propellants have become available, which use hydrofluoroalkane (HFA) instead of CFCs. Patients who previously used CFC devices should be aware that HFA devices may have a different feel or taste compared to their old device. However, this does not mean the medicine is not reaching their lungs.
COMMON INHALER MISTAKES — Only a portion of the medicine sprayed out of any MDI successfully reaches the lungs, even when used properly. Three common problems can further decrease the efficiency of the device and the delivery of inhaled medications: The medication is sprayed out faster than the patient can breathe it in. The patient inhales before finishing the spray of medication. The patient inhales after the medication is sprayed.
Other common mistakes include inhaling through the nose instead of the mouth, squeezing the canister twice but only inhaling once, and forgetting to take the cap off the mouthpiece.
With inhaled corticosteroids, poor technique may also increase the risk of hoarseness and fungal infection (thrush). For this reason, patients are advised to rinse their mouth with water or brush their teeth and tongue after using inhaled steroids.
For people who have persistent difficulty timing their breath with spraying the medication, there are MDIs available that automatically release the medication when the person breathes in (ie, Maxair Autohaler®).
Another alternative patients may discuss with their healthcare provider is the use of dry powder inhalers (DPIs). DPIs eliminate the need to coordinate inhalation and hand movement. DPIs deliver a fine powder to the lungs when the patient breathes in (show figure 3). Patients who use dry powdered inhalers need to inhale more forcefully than is necessary with a traditional aerosol inhaler. Thus, DPIs may not be suitable for the elderly or persons with nerve or muscle weakness. Also, patients must take care not to blow (exhale) directly into the device before breathing in, as this can scatter the medicine before it can be inhaled.
SPACER DEVICES — Medication delivery can be improved by adding a spacer device to the inhaler. A spacer holds the medicine in a chamber after it has been released from the canister, allowing the patient to inhale slowly and deeply once or twice (show figure 2). Spacers can dramatically decrease the amount of medicine deposited in the back of the mouth or on the tongue, allowing much more of the medicine to reach the lungs.
There are many spacers on the market, although little is known about the benefit of one type versus another. In general, larger sized spacers appear to be more effective than smaller ones. Proper technique and frequent cleaning are important to ensure optimal drug delivery. The package insert that comes with the spacer should be read carefully for specific directions about cleaning and use.
Cleaning the spacer — Although the powder residue that is deposited in the chamber is not harmful, it is recommended that the spacer be cleaned periodically. The spacer should be washed with warm water and dishwashing detergent; washing with water alone causes an electrostatic charge to develop, reducing the effectiveness of the spacer.
TECHNIQUE — When using a metered dose inhaler (with or without a spacer): Shake the inhaler for five seconds If using a spacer, place the mouthpiece of the inhaler into the small end of the spacer Position the inhaler with the index finger on the top of the medication canister and the thumb supporting the bottom of the inhaler Place the spacer tube or mouthpiece between the lips Close mouth around spacer or mouthpiece (show figure 4). For spacers that have a mask, hold the mask snugly to the face Exhale normally (not forcefully) Press down the top of the medication canister with the index finger to release the medication At the same time as the canister is pressed, inhale deeply and slowly until the lungs are completely filled; this should take four to six seconds Hold the medication in the lungs for 4 to 10 seconds before exhaling Wait a minimum of 15 seconds before repeating these steps for a second puff Rinse the mouth after using an inhaled steroid, and spit the water out rather than swallowing it
ASTHMA ATTACK CARE AND PREVENTION — Patients with asthma should work with their healthcare provider to ensure that their medication regimen is successful for both treating and preventing asthma attacks. Depending upon the severity of a patient's asthma, the treatment plan may include regular visits with the provider, use of one or more medications, avoiding asthma triggers, and/or home peak flow monitoring. At each visit, patients should demonstrate how they use an inhaler to their healthcare provider to ensure that the correct technique is used. (See "Patient information: Overview of managing asthma" and see "Patient information: How to use a peak flow meter" and see "Patient information: Trigger avoidance in asthma").
Ensuring medication is available — Patients should always have an adequate supply of their medication(s). This includes verifying that medication is not expired and that a spare MDI is available.
Determining when an inhaler is empty — It is not always possible to determine when an MDI canister is empty by shaking it, because some propellant remains in the canister after all of the medication has been used. A few MDIs are now being manufactured with integrated dose counters, including Ventolin-HFA®, available in the United States since June 2006. In the absence of a counter, patients may maintain a log of the number of sprays used. The MDI should be disposed of when the designated number of sprays has been reached, even if it is still possible to continue spraying. In the past, patients have been instructed to drop the canister into a bowl of water and observe how it floats. However, studies have determined that this method is not reliable and it is no longer recommended.
WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two patients are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.
This discussion will be updated as needed every four months on our web site (www.patients.uptodate.com). Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information.
A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable. National Library of Medicine
(www.nlm.nih.gov/medlineplus/healthtopics.html)
National Heart, Lung, and Blood Institute
(www.nhlbi.nih.gov/)
National Lung Health Education Program
(www.nlhep.org)
American Lung Association
(www.lungusa.org)
American Academy of Allergy, Asthma, and Immunology
(www.aaaai.org/patients.stm)
American College of Allergy, Asthma, and Immunology
(www.acaai.org/public/)
[1-3]
Use of UpToDate is subject to the Subscription and License Agreement. REFERENCES 1. Schecker, MH, Wilson, AF, Mukai, DS, et al. A device for overcoming discoordination with metered-dose inhalers. J Allergy Clin Immunol 1993; 92:783.
2. Toogood, JH. Helping your patients make better use of MDIs and spacers. J Respir Dis 1994; 15:151.
3. Melani, AS, Zanchetta, D, Barbato, N, et al. Inhalation technique and variables associated with misuse of conventional metered-dose inhalers and newer dry powder inhalers in experienced adults. Ann Allergy Asthma Immunol 2004; 93:439.
Asthma Patient information: Metered dose inhaler techniques
INTRODUCTION — Inhaled medications are the cornerstone of asthma therapy, but they can only be effective if they are used properly. Correct technique delivers the medication more effectively and leads to better airway responses.The result of poor technique is that little or no medicine reaches the lungs.
Unfortunately, many people with asthma do not use the best inhaler technique. However, studies have shown that almost everyone can learn proper inhaler technique with adequate training and practice.
METERED DOSE INHALERS — Metered dose inhalers (MDIs) are used to deliver a variety of inhaled medications, including quick relief bronchodilators such as Proventil®, Ventolin®, or Alupent®, and controller medicines such as corticosteroids (Flovent®, QVAR®, Pulmicort®, and others) and cromolyn (Intal®). Medications are delivered by pushing down on a canister to release a specific amount of aerosolized medication. An MDI consists of a pressurized canister, a metering valve and stem, and a mouthpiece actuator (show figure 1).
The canister contains the drug suspended in a mixture of propellants, surfactants, preservatives, flavoring agents, and dispersal agents. The propellant has traditionally been a chlorofluorocarbon (CFC). Since the development of an international agreement to ban CFCs, new CFC-free propellants have become available, which use hydrofluoroalkane (HFA) instead of CFCs. Patients who previously used CFC devices should be aware that HFA devices may have a different feel or taste compared to their old device. However, this does not mean the medicine is not reaching their lungs.
COMMON INHALER MISTAKES — Only a portion of the medicine sprayed out of any MDI successfully reaches the lungs, even when used properly. Three common problems can further decrease the efficiency of the device and the delivery of inhaled medications: The medication is sprayed out faster than the patient can breathe it in. The patient inhales before finishing the spray of medication. The patient inhales after the medication is sprayed.
Other common mistakes include inhaling through the nose instead of the mouth, squeezing the canister twice but only inhaling once, and forgetting to take the cap off the mouthpiece.
With inhaled corticosteroids, poor technique may also increase the risk of hoarseness and fungal infection (thrush). For this reason, patients are advised to rinse their mouth with water or brush their teeth and tongue after using inhaled steroids.
For people who have persistent difficulty timing their breath with spraying the medication, there are MDIs available that automatically release the medication when the person breathes in (ie, Maxair Autohaler®).
Another alternative patients may discuss with their healthcare provider is the use of dry powder inhalers (DPIs). DPIs eliminate the need to coordinate inhalation and hand movement. DPIs deliver a fine powder to the lungs when the patient breathes in (show figure 3). Patients who use dry powdered inhalers need to inhale more forcefully than is necessary with a traditional aerosol inhaler. Thus, DPIs may not be suitable for the elderly or persons with nerve or muscle weakness. Also, patients must take care not to blow (exhale) directly into the device before breathing in, as this can scatter the medicine before it can be inhaled.
SPACER DEVICES — Medication delivery can be improved by adding a spacer device to the inhaler. A spacer holds the medicine in a chamber after it has been released from the canister, allowing the patient to inhale slowly and deeply once or twice (show figure 2). Spacers can dramatically decrease the amount of medicine deposited in the back of the mouth or on the tongue, allowing much more of the medicine to reach the lungs.
There are many spacers on the market, although little is known about the benefit of one type versus another. In general, larger sized spacers appear to be more effective than smaller ones. Proper technique and frequent cleaning are important to ensure optimal drug delivery. The package insert that comes with the spacer should be read carefully for specific directions about cleaning and use.
Cleaning the spacer — Although the powder residue that is deposited in the chamber is not harmful, it is recommended that the spacer be cleaned periodically. The spacer should be washed with warm water and dishwashing detergent; washing with water alone causes an electrostatic charge to develop, reducing the effectiveness of the spacer.
TECHNIQUE — When using a metered dose inhaler (with or without a spacer): Shake the inhaler for five seconds If using a spacer, place the mouthpiece of the inhaler into the small end of the spacer Position the inhaler with the index finger on the top of the medication canister and the thumb supporting the bottom of the inhaler Place the spacer tube or mouthpiece between the lips Close mouth around spacer or mouthpiece (show figure 4). For spacers that have a mask, hold the mask snugly to the face Exhale normally (not forcefully) Press down the top of the medication canister with the index finger to release the medication At the same time as the canister is pressed, inhale deeply and slowly until the lungs are completely filled; this should take four to six seconds Hold the medication in the lungs for 4 to 10 seconds before exhaling Wait a minimum of 15 seconds before repeating these steps for a second puff Rinse the mouth after using an inhaled steroid, and spit the water out rather than swallowing it
ASTHMA ATTACK CARE AND PREVENTION — Patients with asthma should work with their healthcare provider to ensure that their medication regimen is successful for both treating and preventing asthma attacks. Depending upon the severity of a patient's asthma, the treatment plan may include regular visits with the provider, use of one or more medications, avoiding asthma triggers, and/or home peak flow monitoring. At each visit, patients should demonstrate how they use an inhaler to their healthcare provider to ensure that the correct technique is used. (See "Patient information: Overview of managing asthma" and see "Patient information: How to use a peak flow meter" and see "Patient information: Trigger avoidance in asthma").
Ensuring medication is available — Patients should always have an adequate supply of their medication(s). This includes verifying that medication is not expired and that a spare MDI is available.
Determining when an inhaler is empty — It is not always possible to determine when an MDI canister is empty by shaking it, because some propellant remains in the canister after all of the medication has been used. A few MDIs are now being manufactured with integrated dose counters, including Ventolin-HFA®, available in the United States since June 2006. In the absence of a counter, patients may maintain a log of the number of sprays used. The MDI should be disposed of when the designated number of sprays has been reached, even if it is still possible to continue spraying. In the past, patients have been instructed to drop the canister into a bowl of water and observe how it floats. However, studies have determined that this method is not reliable and it is no longer recommended.
WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two patients are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.
This discussion will be updated as needed every four months on our web site (www.patients.uptodate.com). Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information.
A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable. National Library of Medicine
(www.nlm.nih.gov/medlineplus/healthtopics.html)
National Heart, Lung, and Blood Institute
(www.nhlbi.nih.gov/)
National Lung Health Education Program
(www.nlhep.org)
American Lung Association
(www.lungusa.org)
American Academy of Allergy, Asthma, and Immunology
(www.aaaai.org/patients.stm)
American College of Allergy, Asthma, and Immunology
(www.acaai.org/public/)
[1-3]
Use of UpToDate is subject to the Subscription and License Agreement. REFERENCES 1. Schecker, MH, Wilson, AF, Mukai, DS, et al. A device for overcoming discoordination with metered-dose inhalers. J Allergy Clin Immunol 1993; 92:783.
2. Toogood, JH. Helping your patients make better use of MDIs and spacers. J Respir Dis 1994; 15:151.
3. Melani, AS, Zanchetta, D, Barbato, N, et al. Inhalation technique and variables associated with misuse of conventional metered-dose inhalers and newer dry powder inhalers in experienced adults. Ann Allergy Asthma Immunol 2004; 93:439.
Unfortunately, many people with asthma do not use the best inhaler technique. However, studies have shown that almost everyone can learn proper inhaler technique with adequate training and practice.
METERED DOSE INHALERS — Metered dose inhalers (MDIs) are used to deliver a variety of inhaled medications, including quick relief bronchodilators such as Proventil®, Ventolin®, or Alupent®, and controller medicines such as corticosteroids (Flovent®, QVAR®, Pulmicort®, and others) and cromolyn (Intal®). Medications are delivered by pushing down on a canister to release a specific amount of aerosolized medication. An MDI consists of a pressurized canister, a metering valve and stem, and a mouthpiece actuator (show figure 1).
The canister contains the drug suspended in a mixture of propellants, surfactants, preservatives, flavoring agents, and dispersal agents. The propellant has traditionally been a chlorofluorocarbon (CFC). Since the development of an international agreement to ban CFCs, new CFC-free propellants have become available, which use hydrofluoroalkane (HFA) instead of CFCs. Patients who previously used CFC devices should be aware that HFA devices may have a different feel or taste compared to their old device. However, this does not mean the medicine is not reaching their lungs.
COMMON INHALER MISTAKES — Only a portion of the medicine sprayed out of any MDI successfully reaches the lungs, even when used properly. Three common problems can further decrease the efficiency of the device and the delivery of inhaled medications: The medication is sprayed out faster than the patient can breathe it in. The patient inhales before finishing the spray of medication. The patient inhales after the medication is sprayed.
Other common mistakes include inhaling through the nose instead of the mouth, squeezing the canister twice but only inhaling once, and forgetting to take the cap off the mouthpiece.
With inhaled corticosteroids, poor technique may also increase the risk of hoarseness and fungal infection (thrush). For this reason, patients are advised to rinse their mouth with water or brush their teeth and tongue after using inhaled steroids.
For people who have persistent difficulty timing their breath with spraying the medication, there are MDIs available that automatically release the medication when the person breathes in (ie, Maxair Autohaler®).
Another alternative patients may discuss with their healthcare provider is the use of dry powder inhalers (DPIs). DPIs eliminate the need to coordinate inhalation and hand movement. DPIs deliver a fine powder to the lungs when the patient breathes in (show figure 3). Patients who use dry powdered inhalers need to inhale more forcefully than is necessary with a traditional aerosol inhaler. Thus, DPIs may not be suitable for the elderly or persons with nerve or muscle weakness. Also, patients must take care not to blow (exhale) directly into the device before breathing in, as this can scatter the medicine before it can be inhaled.
SPACER DEVICES — Medication delivery can be improved by adding a spacer device to the inhaler. A spacer holds the medicine in a chamber after it has been released from the canister, allowing the patient to inhale slowly and deeply once or twice (show figure 2). Spacers can dramatically decrease the amount of medicine deposited in the back of the mouth or on the tongue, allowing much more of the medicine to reach the lungs.
There are many spacers on the market, although little is known about the benefit of one type versus another. In general, larger sized spacers appear to be more effective than smaller ones. Proper technique and frequent cleaning are important to ensure optimal drug delivery. The package insert that comes with the spacer should be read carefully for specific directions about cleaning and use.
Cleaning the spacer — Although the powder residue that is deposited in the chamber is not harmful, it is recommended that the spacer be cleaned periodically. The spacer should be washed with warm water and dishwashing detergent; washing with water alone causes an electrostatic charge to develop, reducing the effectiveness of the spacer.
TECHNIQUE — When using a metered dose inhaler (with or without a spacer): Shake the inhaler for five seconds If using a spacer, place the mouthpiece of the inhaler into the small end of the spacer Position the inhaler with the index finger on the top of the medication canister and the thumb supporting the bottom of the inhaler Place the spacer tube or mouthpiece between the lips Close mouth around spacer or mouthpiece (show figure 4). For spacers that have a mask, hold the mask snugly to the face Exhale normally (not forcefully) Press down the top of the medication canister with the index finger to release the medication At the same time as the canister is pressed, inhale deeply and slowly until the lungs are completely filled; this should take four to six seconds Hold the medication in the lungs for 4 to 10 seconds before exhaling Wait a minimum of 15 seconds before repeating these steps for a second puff Rinse the mouth after using an inhaled steroid, and spit the water out rather than swallowing it
ASTHMA ATTACK CARE AND PREVENTION — Patients with asthma should work with their healthcare provider to ensure that their medication regimen is successful for both treating and preventing asthma attacks. Depending upon the severity of a patient's asthma, the treatment plan may include regular visits with the provider, use of one or more medications, avoiding asthma triggers, and/or home peak flow monitoring. At each visit, patients should demonstrate how they use an inhaler to their healthcare provider to ensure that the correct technique is used. (See "Patient information: Overview of managing asthma" and see "Patient information: How to use a peak flow meter" and see "Patient information: Trigger avoidance in asthma").
Ensuring medication is available — Patients should always have an adequate supply of their medication(s). This includes verifying that medication is not expired and that a spare MDI is available.
Determining when an inhaler is empty — It is not always possible to determine when an MDI canister is empty by shaking it, because some propellant remains in the canister after all of the medication has been used. A few MDIs are now being manufactured with integrated dose counters, including Ventolin-HFA®, available in the United States since June 2006. In the absence of a counter, patients may maintain a log of the number of sprays used. The MDI should be disposed of when the designated number of sprays has been reached, even if it is still possible to continue spraying. In the past, patients have been instructed to drop the canister into a bowl of water and observe how it floats. However, studies have determined that this method is not reliable and it is no longer recommended.
WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two patients are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.
This discussion will be updated as needed every four months on our web site (www.patients.uptodate.com). Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information.
A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable. National Library of Medicine
(www.nlm.nih.gov/medlineplus/healthtopics.html)
National Heart, Lung, and Blood Institute
(www.nhlbi.nih.gov/)
National Lung Health Education Program
(www.nlhep.org)
American Lung Association
(www.lungusa.org)
American Academy of Allergy, Asthma, and Immunology
(www.aaaai.org/patients.stm)
American College of Allergy, Asthma, and Immunology
(www.acaai.org/public/)
[1-3]
Use of UpToDate is subject to the Subscription and License Agreement. REFERENCES 1. Schecker, MH, Wilson, AF, Mukai, DS, et al. A device for overcoming discoordination with metered-dose inhalers. J Allergy Clin Immunol 1993; 92:783.
2. Toogood, JH. Helping your patients make better use of MDIs and spacers. J Respir Dis 1994; 15:151.
3. Melani, AS, Zanchetta, D, Barbato, N, et al. Inhalation technique and variables associated with misuse of conventional metered-dose inhalers and newer dry powder inhalers in experienced adults. Ann Allergy Asthma Immunol 2004; 93:439.
ASTHMA Patient information: How to use a peak flow meter
INTRODUCTION — The management of asthma relies on a patient's ability to monitor their asthma regularly. Self-monitoring includes assessing the frequency and severity of symptoms (such as wheezing and shortness of breath) and measurement of lung function with tests such as a peak expiratory flow rate (PEFR). PEFR provides a number that correlates to how open the lung's airways are; as asthma worsens and the airways narrow, the PEFR decreases. Monitoring can help a patient and their healthcare provider determine the most appropriate asthma treatment plan. (See "Patient information: Overview of managing asthma").
ASTHMA MONITORING RECOMMENDATIONS — The National Asthma Education and Prevention Program (NAEPP) recommends that patients with moderate to severe persistent asthma have a peak flow meter at home and know how to use it [1]. The peak flow meter is small, inexpensive, and easy for most patients to use.
The NAEPP recommend that patients use a peak flow meter to: Provide a regular assessment of lung function and response to treatment over the short- and long-term Determine the severity of an asthma attack Assess response to treatment during an attack
Patients should use an asthma diary to record their daily peak flow meter readings, exposure to potential asthma triggers, asthma medication use, and asthma symptoms (show figure 1). This can help patients to see a cause-and-effect relationship between exposure to triggers and decreases in peak flow. The asthma diary can be reviewed with a healthcare provider to make decisions about asthma treatment. (See "Patient information: Trigger avoidance in asthma" and see "Patient information: Metered dose inhaler techniques").
HOW TO USE A PEAK FLOW METER — PEFR monitoring should be performed on a regular basis, even when asthma symptoms are not present. PEFR should also be checked if symptoms of coughing, wheezing, or shortness of breath develops. Patients should demonstrate PEFR measurement with their healthcare provider to verify that their technique is accurate.
Different brands of peak flow meters have unique features; however, these general instructions can be adapted to an individual's peak flow meter.
Getting the best readings — Several steps are important to make sure the peak flow meter records an accurate value: The peak flow meter should read zero or its lowest reading when not in use Use the peak flow meter while standing up straight Take in as deep a breath as possible Place the peak flow meter in the mouth, with the tongue under the mouthpiece Close the lips tightly around the mouthpiece Blow out as hard and fast as possible Breathe a few normal breaths and then repeat the process two more times. Write down the highest number obtained. Do not average the numbers.
Note: The test should be repeated if the tongue partially blocks the mouthpiece or if the patient coughs or spits during the test. Most peak flow meters need to be cleaned periodically; cleaning instructions should be available when the unit is purchased.
Establishing a baseline measurement — Unlike a blood pressure reading or a cholesterol test, there is no PEFR that is normal for everyone. For this reason, it is important to determine what PEFR value is normal for each individual.
To determine an individual patient's normal PEFR, they should measure their PEFR when they have no asthma symptoms. Three PEFR measurements should be done with the same peak flow meter two to four times daily for two to three weeks. For long term management, most clinicians will recommend testing once per day, usually in the morning.
The patient should note the highest PEFR measure achieved; this is the "personal best" PEFR. This number is used to determine if future PEFR readings are normal or low, and is also used to create a normal PEFR range (between 80 and 100 percent of the personal best PEFR).
Readings below the normal range are a sign of airway narrowing in the lungs. A low PEFR can occur before asthma symptoms such as wheezing or shortness of breath develop.
A personal best PEFR value should be remeasured each year to account for growth (in children) or changes in the disease (in both children and adults). In addition, home PEFR measurements should be verified with readings taken with equipment in a healthcare provider's office since this equipment is more sensitive.
The action plan — Once the normal range can been established, the healthcare provider will provide tailored guidelines (also called an action plan) to follow when the PEFR begins to decrease (show figure 2 and show figure 3).
Peak expiratory flow rates are divided into three zones, which are assigned colors similar to those of a traffic light. These zones can be used to make decisions about the need for treatment: GREEN (80 to 100 percent of personal best) signals that the lungs are functioning well. When readings are within this range and symptoms are not present, patients should continue their regular medicines and activities. YELLOW (50 to 80 percent of personal best) is a sign that the airways in the lungs are somewhat narrowed, making it difficult to move air in and out. A short-term change or increase in medication is generally required. Patients should change or increase their medication to reverse airway narrowing according to the treatment recommendations previously discussed with their provider. RED (below 50 percent of personal best) is a sign that the airways are significantly narrowed and requires immediate treatment. The "rescue" inhaler should be used according to the treatment recommendation previously discussed with the provider. PEFR should be rechecked 10 to 15 minutes after the rescue medication is used. If the PEFR improves, the patient should monitor their PEFR throughout the day. The healthcare provider should be contacted after the patient improves; daily medication may be changed or increased.
EMERGENCY CARE — Patients with asthma who fail to improve or worsen despite treatment require emergency medical services. Severe asthma attacks can be fatal if not treated promptly. In most areas of the United States, 911 can be called for emergency medical assistance. Patients should not attempt to drive to a hospital or clinician's office on their own.
WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two patients are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.
This discussion will be updated as needed every four months on our web site (www.patients.uptodate.com). Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information.
A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable. National Library of Medicine
(www.nlm.nih.gov/medlineplus/healthtopics.html)
National Heart, Lung, and Blood Institute
(www.nhlbi.nih.gov/)
National Lung Health Education Program
(www.nlhep.org)
American Lung Association
(www.lungusa.org)
American Academy of Allergy, Asthma, and Immunology
(www.aaaai.org/patients.stm)
American College of Allergy, Asthma, and Immunology
(www.acaai.org/public/)
[1-6]
Use of UpToDate is subject to the Subscription and License Agreement. REFERENCES 1. National Asthma Education Program Expert Panel. Guidelines for the diagnosis and management of asthma: Update on Selected Topics 2002. US Department of Health and Human Services, National Institutes of Health, Bethesda, (NIH Publication No. 02-5074) June 2003.
2. National Asthma Education Program Expert Panel. Guidelines for the diagnosis and management of asthma. US Department of Health and Human Services, National Institutes of Health, Bethesda, 1997.
3. Ignacio-Garcia, JM, Gonzalez-Santos, P. Asthma self-management education program by home monitoring of peak expiratory flow. Am J Respir Crit Care Med 1995; 151:353.
4. Jones, KP, Mullee, MA, Middleton, M, et al. Peak flow based asthma self-management: a randomised controlled study in general practice. British Thoracic Society Research Committee. Thorax 1995; 50:851.
5. Breathe Well, Live Well: An asthma management program for adults: The American Lung Association 2005.
6. National Asthma Education and Prevention Program. Expert Panel Report: Guidelines for the Diagnosis and Management of Asthma Update on Selected Topics--2002. J Allergy Clin Immunol 2002; 110:S141.
ASTHMA MONITORING RECOMMENDATIONS — The National Asthma Education and Prevention Program (NAEPP) recommends that patients with moderate to severe persistent asthma have a peak flow meter at home and know how to use it [1]. The peak flow meter is small, inexpensive, and easy for most patients to use.
The NAEPP recommend that patients use a peak flow meter to: Provide a regular assessment of lung function and response to treatment over the short- and long-term Determine the severity of an asthma attack Assess response to treatment during an attack
Patients should use an asthma diary to record their daily peak flow meter readings, exposure to potential asthma triggers, asthma medication use, and asthma symptoms (show figure 1). This can help patients to see a cause-and-effect relationship between exposure to triggers and decreases in peak flow. The asthma diary can be reviewed with a healthcare provider to make decisions about asthma treatment. (See "Patient information: Trigger avoidance in asthma" and see "Patient information: Metered dose inhaler techniques").
HOW TO USE A PEAK FLOW METER — PEFR monitoring should be performed on a regular basis, even when asthma symptoms are not present. PEFR should also be checked if symptoms of coughing, wheezing, or shortness of breath develops. Patients should demonstrate PEFR measurement with their healthcare provider to verify that their technique is accurate.
Different brands of peak flow meters have unique features; however, these general instructions can be adapted to an individual's peak flow meter.
Getting the best readings — Several steps are important to make sure the peak flow meter records an accurate value: The peak flow meter should read zero or its lowest reading when not in use Use the peak flow meter while standing up straight Take in as deep a breath as possible Place the peak flow meter in the mouth, with the tongue under the mouthpiece Close the lips tightly around the mouthpiece Blow out as hard and fast as possible Breathe a few normal breaths and then repeat the process two more times. Write down the highest number obtained. Do not average the numbers.
Note: The test should be repeated if the tongue partially blocks the mouthpiece or if the patient coughs or spits during the test. Most peak flow meters need to be cleaned periodically; cleaning instructions should be available when the unit is purchased.
Establishing a baseline measurement — Unlike a blood pressure reading or a cholesterol test, there is no PEFR that is normal for everyone. For this reason, it is important to determine what PEFR value is normal for each individual.
To determine an individual patient's normal PEFR, they should measure their PEFR when they have no asthma symptoms. Three PEFR measurements should be done with the same peak flow meter two to four times daily for two to three weeks. For long term management, most clinicians will recommend testing once per day, usually in the morning.
The patient should note the highest PEFR measure achieved; this is the "personal best" PEFR. This number is used to determine if future PEFR readings are normal or low, and is also used to create a normal PEFR range (between 80 and 100 percent of the personal best PEFR).
Readings below the normal range are a sign of airway narrowing in the lungs. A low PEFR can occur before asthma symptoms such as wheezing or shortness of breath develop.
A personal best PEFR value should be remeasured each year to account for growth (in children) or changes in the disease (in both children and adults). In addition, home PEFR measurements should be verified with readings taken with equipment in a healthcare provider's office since this equipment is more sensitive.
The action plan — Once the normal range can been established, the healthcare provider will provide tailored guidelines (also called an action plan) to follow when the PEFR begins to decrease (show figure 2 and show figure 3).
Peak expiratory flow rates are divided into three zones, which are assigned colors similar to those of a traffic light. These zones can be used to make decisions about the need for treatment: GREEN (80 to 100 percent of personal best) signals that the lungs are functioning well. When readings are within this range and symptoms are not present, patients should continue their regular medicines and activities. YELLOW (50 to 80 percent of personal best) is a sign that the airways in the lungs are somewhat narrowed, making it difficult to move air in and out. A short-term change or increase in medication is generally required. Patients should change or increase their medication to reverse airway narrowing according to the treatment recommendations previously discussed with their provider. RED (below 50 percent of personal best) is a sign that the airways are significantly narrowed and requires immediate treatment. The "rescue" inhaler should be used according to the treatment recommendation previously discussed with the provider. PEFR should be rechecked 10 to 15 minutes after the rescue medication is used. If the PEFR improves, the patient should monitor their PEFR throughout the day. The healthcare provider should be contacted after the patient improves; daily medication may be changed or increased.
EMERGENCY CARE — Patients with asthma who fail to improve or worsen despite treatment require emergency medical services. Severe asthma attacks can be fatal if not treated promptly. In most areas of the United States, 911 can be called for emergency medical assistance. Patients should not attempt to drive to a hospital or clinician's office on their own.
WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two patients are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.
This discussion will be updated as needed every four months on our web site (www.patients.uptodate.com). Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information.
A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable. National Library of Medicine
(www.nlm.nih.gov/medlineplus/healthtopics.html)
National Heart, Lung, and Blood Institute
(www.nhlbi.nih.gov/)
National Lung Health Education Program
(www.nlhep.org)
American Lung Association
(www.lungusa.org)
American Academy of Allergy, Asthma, and Immunology
(www.aaaai.org/patients.stm)
American College of Allergy, Asthma, and Immunology
(www.acaai.org/public/)
[1-6]
Use of UpToDate is subject to the Subscription and License Agreement. REFERENCES 1. National Asthma Education Program Expert Panel. Guidelines for the diagnosis and management of asthma: Update on Selected Topics 2002. US Department of Health and Human Services, National Institutes of Health, Bethesda, (NIH Publication No. 02-5074) June 2003.
2. National Asthma Education Program Expert Panel. Guidelines for the diagnosis and management of asthma. US Department of Health and Human Services, National Institutes of Health, Bethesda, 1997.
3. Ignacio-Garcia, JM, Gonzalez-Santos, P. Asthma self-management education program by home monitoring of peak expiratory flow. Am J Respir Crit Care Med 1995; 151:353.
4. Jones, KP, Mullee, MA, Middleton, M, et al. Peak flow based asthma self-management: a randomised controlled study in general practice. British Thoracic Society Research Committee. Thorax 1995; 50:851.
5. Breathe Well, Live Well: An asthma management program for adults: The American Lung Association 2005.
6. National Asthma Education and Prevention Program. Expert Panel Report: Guidelines for the Diagnosis and Management of Asthma Update on Selected Topics--2002. J Allergy Clin Immunol 2002; 110:S141.
ASTHMA Patient information: How to use a peak flow meter
INTRODUCTION — The management of asthma relies on a patient's ability to monitor their asthma regularly. Self-monitoring includes assessing the frequency and severity of symptoms (such as wheezing and shortness of breath) and measurement of lung function with tests such as a peak expiratory flow rate (PEFR). PEFR provides a number that correlates to how open the lung's airways are; as asthma worsens and the airways narrow, the PEFR decreases. Monitoring can help a patient and their healthcare provider determine the most appropriate asthma treatment plan. (See "Patient information: Overview of managing asthma").
ASTHMA MONITORING RECOMMENDATIONS — The National Asthma Education and Prevention Program (NAEPP) recommends that patients with moderate to severe persistent asthma have a peak flow meter at home and know how to use it [1]. The peak flow meter is small, inexpensive, and easy for most patients to use.
The NAEPP recommend that patients use a peak flow meter to: Provide a regular assessment of lung function and response to treatment over the short- and long-term Determine the severity of an asthma attack Assess response to treatment during an attack
Patients should use an asthma diary to record their daily peak flow meter readings, exposure to potential asthma triggers, asthma medication use, and asthma symptoms (show figure 1). This can help patients to see a cause-and-effect relationship between exposure to triggers and decreases in peak flow. The asthma diary can be reviewed with a healthcare provider to make decisions about asthma treatment. (See "Patient information: Trigger avoidance in asthma" and see "Patient information: Metered dose inhaler techniques").
HOW TO USE A PEAK FLOW METER — PEFR monitoring should be performed on a regular basis, even when asthma symptoms are not present. PEFR should also be checked if symptoms of coughing, wheezing, or shortness of breath develops. Patients should demonstrate PEFR measurement with their healthcare provider to verify that their technique is accurate.
Different brands of peak flow meters have unique features; however, these general instructions can be adapted to an individual's peak flow meter.
Getting the best readings — Several steps are important to make sure the peak flow meter records an accurate value: The peak flow meter should read zero or its lowest reading when not in use Use the peak flow meter while standing up straight Take in as deep a breath as possible Place the peak flow meter in the mouth, with the tongue under the mouthpiece Close the lips tightly around the mouthpiece Blow out as hard and fast as possible Breathe a few normal breaths and then repeat the process two more times. Write down the highest number obtained. Do not average the numbers.
Note: The test should be repeated if the tongue partially blocks the mouthpiece or if the patient coughs or spits during the test. Most peak flow meters need to be cleaned periodically; cleaning instructions should be available when the unit is purchased.
Establishing a baseline measurement — Unlike a blood pressure reading or a cholesterol test, there is no PEFR that is normal for everyone. For this reason, it is important to determine what PEFR value is normal for each individual.
To determine an individual patient's normal PEFR, they should measure their PEFR when they have no asthma symptoms. Three PEFR measurements should be done with the same peak flow meter two to four times daily for two to three weeks. For long term management, most clinicians will recommend testing once per day, usually in the morning.
The patient should note the highest PEFR measure achieved; this is the "personal best" PEFR. This number is used to determine if future PEFR readings are normal or low, and is also used to create a normal PEFR range (between 80 and 100 percent of the personal best PEFR).
Readings below the normal range are a sign of airway narrowing in the lungs. A low PEFR can occur before asthma symptoms such as wheezing or shortness of breath develop.
A personal best PEFR value should be remeasured each year to account for growth (in children) or changes in the disease (in both children and adults). In addition, home PEFR measurements should be verified with readings taken with equipment in a healthcare provider's office since this equipment is more sensitive.
The action plan — Once the normal range can been established, the healthcare provider will provide tailored guidelines (also called an action plan) to follow when the PEFR begins to decrease (show figure 2 and show figure 3).
Peak expiratory flow rates are divided into three zones, which are assigned colors similar to those of a traffic light. These zones can be used to make decisions about the need for treatment: GREEN (80 to 100 percent of personal best) signals that the lungs are functioning well. When readings are within this range and symptoms are not present, patients should continue their regular medicines and activities. YELLOW (50 to 80 percent of personal best) is a sign that the airways in the lungs are somewhat narrowed, making it difficult to move air in and out. A short-term change or increase in medication is generally required. Patients should change or increase their medication to reverse airway narrowing according to the treatment recommendations previously discussed with their provider. RED (below 50 percent of personal best) is a sign that the airways are significantly narrowed and requires immediate treatment. The "rescue" inhaler should be used according to the treatment recommendation previously discussed with the provider. PEFR should be rechecked 10 to 15 minutes after the rescue medication is used. If the PEFR improves, the patient should monitor their PEFR throughout the day. The healthcare provider should be contacted after the patient improves; daily medication may be changed or increased.
EMERGENCY CARE — Patients with asthma who fail to improve or worsen despite treatment require emergency medical services. Severe asthma attacks can be fatal if not treated promptly. In most areas of the United States, 911 can be called for emergency medical assistance. Patients should not attempt to drive to a hospital or clinician's office on their own.
WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two patients are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.
This discussion will be updated as needed every four months on our web site (www.patients.uptodate.com). Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information.
A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable. National Library of Medicine
(www.nlm.nih.gov/medlineplus/healthtopics.html)
National Heart, Lung, and Blood Institute
(www.nhlbi.nih.gov/)
National Lung Health Education Program
(www.nlhep.org)
American Lung Association
(www.lungusa.org)
American Academy of Allergy, Asthma, and Immunology
(www.aaaai.org/patients.stm)
American College of Allergy, Asthma, and Immunology
(www.acaai.org/public/)
[1-6]
Use of UpToDate is subject to the Subscription and License Agreement. REFERENCES 1. National Asthma Education Program Expert Panel. Guidelines for the diagnosis and management of asthma: Update on Selected Topics 2002. US Department of Health and Human Services, National Institutes of Health, Bethesda, (NIH Publication No. 02-5074) June 2003.
2. National Asthma Education Program Expert Panel. Guidelines for the diagnosis and management of asthma. US Department of Health and Human Services, National Institutes of Health, Bethesda, 1997.
3. Ignacio-Garcia, JM, Gonzalez-Santos, P. Asthma self-management education program by home monitoring of peak expiratory flow. Am J Respir Crit Care Med 1995; 151:353.
4. Jones, KP, Mullee, MA, Middleton, M, et al. Peak flow based asthma self-management: a randomised controlled study in general practice. British Thoracic Society Research Committee. Thorax 1995; 50:851.
5. Breathe Well, Live Well: An asthma management program for adults: The American Lung Association 2005.
6. National Asthma Education and Prevention Program. Expert Panel Report: Guidelines for the Diagnosis and Management of Asthma Update on Selected Topics--2002. J Allergy Clin Immunol 2002; 110:S141.
ASTHMA MONITORING RECOMMENDATIONS — The National Asthma Education and Prevention Program (NAEPP) recommends that patients with moderate to severe persistent asthma have a peak flow meter at home and know how to use it [1]. The peak flow meter is small, inexpensive, and easy for most patients to use.
The NAEPP recommend that patients use a peak flow meter to: Provide a regular assessment of lung function and response to treatment over the short- and long-term Determine the severity of an asthma attack Assess response to treatment during an attack
Patients should use an asthma diary to record their daily peak flow meter readings, exposure to potential asthma triggers, asthma medication use, and asthma symptoms (show figure 1). This can help patients to see a cause-and-effect relationship between exposure to triggers and decreases in peak flow. The asthma diary can be reviewed with a healthcare provider to make decisions about asthma treatment. (See "Patient information: Trigger avoidance in asthma" and see "Patient information: Metered dose inhaler techniques").
HOW TO USE A PEAK FLOW METER — PEFR monitoring should be performed on a regular basis, even when asthma symptoms are not present. PEFR should also be checked if symptoms of coughing, wheezing, or shortness of breath develops. Patients should demonstrate PEFR measurement with their healthcare provider to verify that their technique is accurate.
Different brands of peak flow meters have unique features; however, these general instructions can be adapted to an individual's peak flow meter.
Getting the best readings — Several steps are important to make sure the peak flow meter records an accurate value: The peak flow meter should read zero or its lowest reading when not in use Use the peak flow meter while standing up straight Take in as deep a breath as possible Place the peak flow meter in the mouth, with the tongue under the mouthpiece Close the lips tightly around the mouthpiece Blow out as hard and fast as possible Breathe a few normal breaths and then repeat the process two more times. Write down the highest number obtained. Do not average the numbers.
Note: The test should be repeated if the tongue partially blocks the mouthpiece or if the patient coughs or spits during the test. Most peak flow meters need to be cleaned periodically; cleaning instructions should be available when the unit is purchased.
Establishing a baseline measurement — Unlike a blood pressure reading or a cholesterol test, there is no PEFR that is normal for everyone. For this reason, it is important to determine what PEFR value is normal for each individual.
To determine an individual patient's normal PEFR, they should measure their PEFR when they have no asthma symptoms. Three PEFR measurements should be done with the same peak flow meter two to four times daily for two to three weeks. For long term management, most clinicians will recommend testing once per day, usually in the morning.
The patient should note the highest PEFR measure achieved; this is the "personal best" PEFR. This number is used to determine if future PEFR readings are normal or low, and is also used to create a normal PEFR range (between 80 and 100 percent of the personal best PEFR).
Readings below the normal range are a sign of airway narrowing in the lungs. A low PEFR can occur before asthma symptoms such as wheezing or shortness of breath develop.
A personal best PEFR value should be remeasured each year to account for growth (in children) or changes in the disease (in both children and adults). In addition, home PEFR measurements should be verified with readings taken with equipment in a healthcare provider's office since this equipment is more sensitive.
The action plan — Once the normal range can been established, the healthcare provider will provide tailored guidelines (also called an action plan) to follow when the PEFR begins to decrease (show figure 2 and show figure 3).
Peak expiratory flow rates are divided into three zones, which are assigned colors similar to those of a traffic light. These zones can be used to make decisions about the need for treatment: GREEN (80 to 100 percent of personal best) signals that the lungs are functioning well. When readings are within this range and symptoms are not present, patients should continue their regular medicines and activities. YELLOW (50 to 80 percent of personal best) is a sign that the airways in the lungs are somewhat narrowed, making it difficult to move air in and out. A short-term change or increase in medication is generally required. Patients should change or increase their medication to reverse airway narrowing according to the treatment recommendations previously discussed with their provider. RED (below 50 percent of personal best) is a sign that the airways are significantly narrowed and requires immediate treatment. The "rescue" inhaler should be used according to the treatment recommendation previously discussed with the provider. PEFR should be rechecked 10 to 15 minutes after the rescue medication is used. If the PEFR improves, the patient should monitor their PEFR throughout the day. The healthcare provider should be contacted after the patient improves; daily medication may be changed or increased.
EMERGENCY CARE — Patients with asthma who fail to improve or worsen despite treatment require emergency medical services. Severe asthma attacks can be fatal if not treated promptly. In most areas of the United States, 911 can be called for emergency medical assistance. Patients should not attempt to drive to a hospital or clinician's office on their own.
WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two patients are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.
This discussion will be updated as needed every four months on our web site (www.patients.uptodate.com). Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information.
A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable. National Library of Medicine
(www.nlm.nih.gov/medlineplus/healthtopics.html)
National Heart, Lung, and Blood Institute
(www.nhlbi.nih.gov/)
National Lung Health Education Program
(www.nlhep.org)
American Lung Association
(www.lungusa.org)
American Academy of Allergy, Asthma, and Immunology
(www.aaaai.org/patients.stm)
American College of Allergy, Asthma, and Immunology
(www.acaai.org/public/)
[1-6]
Use of UpToDate is subject to the Subscription and License Agreement. REFERENCES 1. National Asthma Education Program Expert Panel. Guidelines for the diagnosis and management of asthma: Update on Selected Topics 2002. US Department of Health and Human Services, National Institutes of Health, Bethesda, (NIH Publication No. 02-5074) June 2003.
2. National Asthma Education Program Expert Panel. Guidelines for the diagnosis and management of asthma. US Department of Health and Human Services, National Institutes of Health, Bethesda, 1997.
3. Ignacio-Garcia, JM, Gonzalez-Santos, P. Asthma self-management education program by home monitoring of peak expiratory flow. Am J Respir Crit Care Med 1995; 151:353.
4. Jones, KP, Mullee, MA, Middleton, M, et al. Peak flow based asthma self-management: a randomised controlled study in general practice. British Thoracic Society Research Committee. Thorax 1995; 50:851.
5. Breathe Well, Live Well: An asthma management program for adults: The American Lung Association 2005.
6. National Asthma Education and Prevention Program. Expert Panel Report: Guidelines for the Diagnosis and Management of Asthma Update on Selected Topics--2002. J Allergy Clin Immunol 2002; 110:S141.
ASTHMA Patient information: Use of an epinephrine autoinjector
INTRODUCTION — Allergic reactions can be triggered by foods, medications, exercise, latex, insect stings, or unknown triggers, and can cause a sudden, potentially life-threatening allergic reaction called anaphylaxis. Epinephrine (also known as adrenaline) is a medicine that treats the symptoms of serious allergic reactions. (See "Patient information: Anaphylaxis").
PATIENT AND FAMILY EDUCATION — A person with allergies, as well as his or her family, close friends, teachers, and co-workers, should learn to use an epinephrine autoinjector before it is needed. Persons suffering with anaphylaxis may panic and be unable to assist with their own injection. In addition, a quick response is necessary to prevent serious complications of anaphylaxis.
Patients should fill their epinephrine autoinjector prescription immediately, and should keep at least one epinephrine autoinjector with them at all times. It is a good idea to have an additional autoinjector at work, school, and home. Family and friends should be informed about where the home injector is stored, and it should be kept in a place that can be easily located by others in an emergency. It is also important to ensure that the injector is not expired, although an expired injector may be used if there is no alternative.
Epinephrine should be stored at normal room temperature, away from cold and heat sources. The epinephrine cartridge window should be examined periodically, to ensure that the solution is colorless and contains no floating particles. Solutions that are discolored or contain particles should be replaced.
SYMPTOMS OF ALLERGY — Allergic reaction can produce symptoms throughout the body. Skin: A sudden tingling and warm sensation, itching, flushing, urticaria (hives), and angioedema (swelling). Eyes: Itching, tearing, and swelling of the tissues around the eyes. Nose and mouth: Sneezing, runny nose, nasal congestion, itching of the mouth, and a metallic taste. Lungs and throat: Difficulty breathing, coughing, wheezing, increased airway secretions, swelling of the upper throat, hoarseness, sounds of labored breathing, and a sensation of choking. Heart: Very rapid heartbeat, arrhythmia (an irregular heart beat), low blood pressure, and cardiac arrest (a cessation of the heart's pumping action). Digestive system: Nausea, vomiting, abdominal cramps, bloating, and diarrhea. Nervous system: Dizziness, weakness, fainting, and a sense of impending doom.
WHEN TO TREAT — Persons having an allergic reaction should use their epinephrine autoinjector immediately if they: Are having trouble breathing Feel tightness in the throat Feel they might pass out
If treating a child with an allergic reaction, also use the autoinjector if the child: Is not responding or seems groggy during an allergic reaction Has food allergies and is vomiting repeatedly shortly after eating, especially if these symptoms are accompanied by flushing or hives
HOW TO TREAT — Patients should read the instructions provided with their autoinjector, and should review them each time a refill is obtained in case changes have been made. Instructions may differ from one autoinjector to another.
Epipen® or Epipen Jr.®
Sit down or lie down if possible. Stay with other people if possible. There is no need to undress, as the injector works through clothing.
1. Unscrew the cap and remove the pen from its case (show picture 1). Keep fingers away from both ends to avoid sticking them. The black end contains the needle.
2. Pull off the gray safety-release cap and form a fist around the auto-injector. The black tip should be pointing down.
3. Swing and quickly jab the black tip into the upper, outer thigh muscle and hold in place for 10 seconds to allow all the medicine to be injected (show figure 1). The cartridge window will show red.
4. Remove the pen.
5. Massage the injected area for 10 seconds.
6. Call 911 and get to the nearest emergency department immediately (patients should not drive themselves). Allergic reactions sometimes come back.
7. Replace the pen in the case, and take it to the hospital.
The Epipen® is now availabe in packages of two, in case a second dose is needed. Large-sized adults may need to repeat the dose. A second dose may also be needed if symptoms are not improving or getting worse after five minutes, or if symptoms come back before reaching the emergency department.
Twinject®
Sit down or lie down if possible. Stay with other people if possible. There is no need to undress, as the injector works through clothing.
1. Remove the pen from its grey case, keeping your fingers off both ends to avoid sticking your finger (show picture 2).
2. Pull off the green cap, labeled "1". This will reveal a grey tip, which contains a needle inside.
3. Pull off the red cap, labeled "2".
4. Form a fist around the autoinjector with the grey tip pointing down.
5. Place the grey tip against the upper, outer thigh, and press firmly until the needle enters the skin. Hold in place for 10 seconds to allow all the medicine to be injected (show figure 1).
6. Remove the injector and check the grey cap. If the needle is visible, epinephrine was given. If the needle is not present, repeat steps 4 through 5 again.
7. Massage the injected area for 10 seconds.
8. Call 911 and get to the nearest emergency department immediately (Patients should not drive themselves). Allergic reactions sometimes come back.
9. Take the pen to the hospital.
The Twinject® contains a second dose inside the cartridge. Large-sized adults may need to repeat the dose. A second dose may be needed if symptoms are not improving or getting worse after five minutes, or if symptoms come back before reaching the emergency department. Studies have shown that one in three patients will need a second dose.
To remove the inside injector: Unscrew the grey cap, taking care to avoid the needle. Hold the blue ring and pull the small injector out.
To use the second dose: Slide the yellow or orange collar off plunger at the other end. Quickly jab the injector firmly into your thigh muscle; push the plunger all the way down to inject the medicine. Remove the injector.
Injector disposal — Injectors should not be thrown away with household trash since they contain a needle. Patients should take their used injectors to a hospital or healthcare provider for proper disposal.
SIDE EFFECTS — The benefits of epinephrine in treatment of a severe allergic reaction far outweigh the risks of side effects. However, epinephrine can cause short-lived side effects in some patients. The most common side effects include the following:
Heart — Fast and/or pounding heartbeat, fleeting chest pain
Nervous system — Nervousness, trembling, feeling cold, anxiety, headache, dizziness
Digestive system — Nausea, dry throat
Lungs — Fleeting shortness of breath
FOLLOW-UP CARE — Patients can have varying responses to a severe allergic reaction. Some patients have symptoms that will resolve rapidly and completely with treatment. These patients may feel fatigued, but otherwise normal afterwards. Other patients have symptoms that take longer to resolve. For most patients, facial swelling and asthma symptoms resolve completely after 24 to 48 hours.
Some patients experience a second reaction after the initial allergic reaction, although this is not common. Second reactions can occur hours to up to four days later, although most second reactions happen within eight hours.
In most cases, the doctor may advise taking antihistamines regularly for several days after the allergic reaction. Oral corticosteroids, a type of medication that reduces inflammation, may also be prescribed. Antihistamines and corticosteroids are prescribed to treat residual symptoms; it is also possible (but not proven) that these medications can help to prevent a second reaction.
WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two patients are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.
This discussion will be updated as needed every four months on our web site (www.patients.uptodate.com). Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information.
A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable. The Food Allergy and Anaphylaxis Network
(www.foodallergy.org)
American Academy of Allergy, Asthma, and Immunology
(www.aaaai.org)
Anaphylaxis Foundation and Anaphylaxis Network of Canada
(www.anaphylaxis.org)
The Anaphylaxis Campaign
(www.anaphylaxis.org.uk)
[1-7]
Use of UpToDate is subject to the Subscription and License Agreement. REFERENCES 1. Bochner, BS, Lichtenstein, LM. Anaphylaxis. N Engl J Med 1991; 324:1785.
2. Ewan, PW. Anaphylaxis. BMJ 1998; 316:1442.
3. Fisher, M. Treatment of acute anaphylaxis. BMJ 1995; 311:731.
4. Kemp, SF, Lockey, RF, Wolf, BL, Lieberman, P. Anaphylaxis: Review of 266 cases. Arch Intern Med 1995; 155:1749.
5. Chamberlain, D. Emergency medical treatment of anaphylactic reactions. Project Team of the Resuscitation Council (UK). J Accid Emerg Med 1999; 16:243.
6. Golden, DB. Patterns of anaphylaxis: acute and late phase features of allergic reactions. Novartis Found Symp 2004; 257:101.
7. Pumphrey, R. Anaphylaxis: can we tell who is at risk of a fatal reaction?. Curr Opin Allergy Clin Immunol 2004; 4:285.
PATIENT AND FAMILY EDUCATION — A person with allergies, as well as his or her family, close friends, teachers, and co-workers, should learn to use an epinephrine autoinjector before it is needed. Persons suffering with anaphylaxis may panic and be unable to assist with their own injection. In addition, a quick response is necessary to prevent serious complications of anaphylaxis.
Patients should fill their epinephrine autoinjector prescription immediately, and should keep at least one epinephrine autoinjector with them at all times. It is a good idea to have an additional autoinjector at work, school, and home. Family and friends should be informed about where the home injector is stored, and it should be kept in a place that can be easily located by others in an emergency. It is also important to ensure that the injector is not expired, although an expired injector may be used if there is no alternative.
Epinephrine should be stored at normal room temperature, away from cold and heat sources. The epinephrine cartridge window should be examined periodically, to ensure that the solution is colorless and contains no floating particles. Solutions that are discolored or contain particles should be replaced.
SYMPTOMS OF ALLERGY — Allergic reaction can produce symptoms throughout the body. Skin: A sudden tingling and warm sensation, itching, flushing, urticaria (hives), and angioedema (swelling). Eyes: Itching, tearing, and swelling of the tissues around the eyes. Nose and mouth: Sneezing, runny nose, nasal congestion, itching of the mouth, and a metallic taste. Lungs and throat: Difficulty breathing, coughing, wheezing, increased airway secretions, swelling of the upper throat, hoarseness, sounds of labored breathing, and a sensation of choking. Heart: Very rapid heartbeat, arrhythmia (an irregular heart beat), low blood pressure, and cardiac arrest (a cessation of the heart's pumping action). Digestive system: Nausea, vomiting, abdominal cramps, bloating, and diarrhea. Nervous system: Dizziness, weakness, fainting, and a sense of impending doom.
WHEN TO TREAT — Persons having an allergic reaction should use their epinephrine autoinjector immediately if they: Are having trouble breathing Feel tightness in the throat Feel they might pass out
If treating a child with an allergic reaction, also use the autoinjector if the child: Is not responding or seems groggy during an allergic reaction Has food allergies and is vomiting repeatedly shortly after eating, especially if these symptoms are accompanied by flushing or hives
HOW TO TREAT — Patients should read the instructions provided with their autoinjector, and should review them each time a refill is obtained in case changes have been made. Instructions may differ from one autoinjector to another.
Epipen® or Epipen Jr.®
Sit down or lie down if possible. Stay with other people if possible. There is no need to undress, as the injector works through clothing.
1. Unscrew the cap and remove the pen from its case (show picture 1). Keep fingers away from both ends to avoid sticking them. The black end contains the needle.
2. Pull off the gray safety-release cap and form a fist around the auto-injector. The black tip should be pointing down.
3. Swing and quickly jab the black tip into the upper, outer thigh muscle and hold in place for 10 seconds to allow all the medicine to be injected (show figure 1). The cartridge window will show red.
4. Remove the pen.
5. Massage the injected area for 10 seconds.
6. Call 911 and get to the nearest emergency department immediately (patients should not drive themselves). Allergic reactions sometimes come back.
7. Replace the pen in the case, and take it to the hospital.
The Epipen® is now availabe in packages of two, in case a second dose is needed. Large-sized adults may need to repeat the dose. A second dose may also be needed if symptoms are not improving or getting worse after five minutes, or if symptoms come back before reaching the emergency department.
Twinject®
Sit down or lie down if possible. Stay with other people if possible. There is no need to undress, as the injector works through clothing.
1. Remove the pen from its grey case, keeping your fingers off both ends to avoid sticking your finger (show picture 2).
2. Pull off the green cap, labeled "1". This will reveal a grey tip, which contains a needle inside.
3. Pull off the red cap, labeled "2".
4. Form a fist around the autoinjector with the grey tip pointing down.
5. Place the grey tip against the upper, outer thigh, and press firmly until the needle enters the skin. Hold in place for 10 seconds to allow all the medicine to be injected (show figure 1).
6. Remove the injector and check the grey cap. If the needle is visible, epinephrine was given. If the needle is not present, repeat steps 4 through 5 again.
7. Massage the injected area for 10 seconds.
8. Call 911 and get to the nearest emergency department immediately (Patients should not drive themselves). Allergic reactions sometimes come back.
9. Take the pen to the hospital.
The Twinject® contains a second dose inside the cartridge. Large-sized adults may need to repeat the dose. A second dose may be needed if symptoms are not improving or getting worse after five minutes, or if symptoms come back before reaching the emergency department. Studies have shown that one in three patients will need a second dose.
To remove the inside injector: Unscrew the grey cap, taking care to avoid the needle. Hold the blue ring and pull the small injector out.
To use the second dose: Slide the yellow or orange collar off plunger at the other end. Quickly jab the injector firmly into your thigh muscle; push the plunger all the way down to inject the medicine. Remove the injector.
Injector disposal — Injectors should not be thrown away with household trash since they contain a needle. Patients should take their used injectors to a hospital or healthcare provider for proper disposal.
SIDE EFFECTS — The benefits of epinephrine in treatment of a severe allergic reaction far outweigh the risks of side effects. However, epinephrine can cause short-lived side effects in some patients. The most common side effects include the following:
Heart — Fast and/or pounding heartbeat, fleeting chest pain
Nervous system — Nervousness, trembling, feeling cold, anxiety, headache, dizziness
Digestive system — Nausea, dry throat
Lungs — Fleeting shortness of breath
FOLLOW-UP CARE — Patients can have varying responses to a severe allergic reaction. Some patients have symptoms that will resolve rapidly and completely with treatment. These patients may feel fatigued, but otherwise normal afterwards. Other patients have symptoms that take longer to resolve. For most patients, facial swelling and asthma symptoms resolve completely after 24 to 48 hours.
Some patients experience a second reaction after the initial allergic reaction, although this is not common. Second reactions can occur hours to up to four days later, although most second reactions happen within eight hours.
In most cases, the doctor may advise taking antihistamines regularly for several days after the allergic reaction. Oral corticosteroids, a type of medication that reduces inflammation, may also be prescribed. Antihistamines and corticosteroids are prescribed to treat residual symptoms; it is also possible (but not proven) that these medications can help to prevent a second reaction.
WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two patients are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.
This discussion will be updated as needed every four months on our web site (www.patients.uptodate.com). Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information.
A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable. The Food Allergy and Anaphylaxis Network
(www.foodallergy.org)
American Academy of Allergy, Asthma, and Immunology
(www.aaaai.org)
Anaphylaxis Foundation and Anaphylaxis Network of Canada
(www.anaphylaxis.org)
The Anaphylaxis Campaign
(www.anaphylaxis.org.uk)
[1-7]
Use of UpToDate is subject to the Subscription and License Agreement. REFERENCES 1. Bochner, BS, Lichtenstein, LM. Anaphylaxis. N Engl J Med 1991; 324:1785.
2. Ewan, PW. Anaphylaxis. BMJ 1998; 316:1442.
3. Fisher, M. Treatment of acute anaphylaxis. BMJ 1995; 311:731.
4. Kemp, SF, Lockey, RF, Wolf, BL, Lieberman, P. Anaphylaxis: Review of 266 cases. Arch Intern Med 1995; 155:1749.
5. Chamberlain, D. Emergency medical treatment of anaphylactic reactions. Project Team of the Resuscitation Council (UK). J Accid Emerg Med 1999; 16:243.
6. Golden, DB. Patterns of anaphylaxis: acute and late phase features of allergic reactions. Novartis Found Symp 2004; 257:101.
7. Pumphrey, R. Anaphylaxis: can we tell who is at risk of a fatal reaction?. Curr Opin Allergy Clin Immunol 2004; 4:285.
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