Asthma in Women
Asthma in Pregnancy

Definition and Causes of Asthma

Twenty percent of the U.S. population has allergies or asthma (6).

Asthma is a disease of chronic inflammation of the airways (the tubes bringing air to the lungs). The inflammation makes breathing difficult. How asthma affects a person fluctuates with a person's various environmental and medical conditions. Asthma can be life-threatening. It is not contagious. Symptoms can start at any age.

Asthma is defined as a chronic inflammatory disease of the airways (2), the airways being the tubes in the lungs that bring in critical supplies of oxygen from the air into the body. It is included in one of the two major categories lung diseases called obstructive lung diseases, also included is chronic obstructive pulmonary disease usually caused by smoking. These obstructive lung diseases are conditions in which the air can come in, but the exit of air, called expiration, is impaired, in other words obstructed or blocked. The cause of this blockage is usually narrowed airways and increased mucus.

In asthma, a person's lungs react excessively to many triggers (stimuli). Frequently, an asthmatic person is also allergic, and the allergic trigger is the cause of an asthma attack. Other causes of asthma attacks (also called exacerbations) include smoking, environmental pollution, exercise, and upper respiratory infections, such as the common cold or bronchitis. Viral infections are being increasingly recognized as major triggers of asthma attacks. These infections may be found in the future to be even more important than other asthma triggers. Although the attacks can last for only minutes before resolving, sometimes acute asthma exacerbations last for days or weeks. They can even be fatal.

It is becoming more and more clear that asthma and gastroesophageal reflux can often occur in the same person. Gastroesophageal reflux is a condition of irritation and inflammation of the esophagus due to contact of the stomach contents with the lining of the esophagus. Although the cause and effect of how asthma and reflux are related are blurry, in terms of which one triggers the other, when the two conditions (not infrequently) occur in the same person they can trigger each other.

There may be genetic component to asthma, meaning that the built-in messages physically passed on from birth from our parents may play a role. It has long been observed that asthma sometimes "runs in families". Already genes causing susceptibility to asthma in such families are being discovered.

Asthma can occur in pregnancy and requires very close monitoring during that time. Asthma can even begin during pregnancy. Three to five percent of all pregnant women have asthma (11).

The Magnitude of the Problem

Asthma is responsible for:

  • Restricted days - over 100 millions days annually)
  • Huge costs - total annual costs of $6.2 billion
  • Deaths - 5,000 asthma-related deaths in the U.S. each year

The National Asthma Education and Prevention Program (NAEPP) started in 1989 with the goal of raising awareness about the seriousness of asthma as a chronic disease, as well as improving recognition of symptoms of asthma by doctors and the public. The NAEPP is run by the National Heart, Lung, and Blood Institute. Statistics about asthma, including those above, can be obtained from the NAEPP.

Between 12 and 15 million people in the U.S. have asthma (7). One 1998 estimate from the Centers for Disease Control, was even higher at 17 million. In 1998, asthma cost the U.S. $11.3 billion (2).

Diagnosis (Symptoms): How Does a Woman Know She Has Asthma?

There are many hints that a woman has asthma, but she may not recognize it as asthma. Understanding the symptoms is easier after realizing what is actually happening during the attack.

A few major things happen during an asthma attack. First of all, the muscles lining the airways spasm, meaning tighten up, and this causes the tubes to become narrow. Secondly, to make matters worse, more mucus is produced than usual. The mucus can block the flow of air in the already narrow tubes. These changes are responsible for the symptoms of asthma, the hints that someone has asthma. The inflammation causes wheezing, breathlessness, chest tightness, and cough, which tend to be worse in the night and early morning. Asthmatics tend to be more sensitive to things that generally irritate the airways, like heavy scents and smoke. Sometimes people have disrupted sleep from asthma because they wake up with coughing or trouble breathing. Asthma can get better, stay the same, or get worse with time. It is pretty much impossible to predict what will happen years down the road in a given person.


What is Asthma? Asthma Myths Debunked See Slideshow

Asthma attacks can be mild, moderate, or severe. Fortunately, they only rarely lead to death. Mild or moderate attacks may show up as coughing, chest tightness, or a wheezing (whistling type of noise) during breathing. Any one person can have any one or a combination of these symptoms.

Many people do not know that coughing by itself can be a symptom of asthma. In fact, asthma is one of the three top causes of chronic cough. Also, many people only experience symptoms of asthma with a viral respiratory infection, as during a bad cold. Alternatively, asthma may show up as a cough that occurs only during or after exercise.

In severe attacks, the woman feels short of breath, has trouble talking, and may notice retraction (sucking in) of the muscles surrounding the ribs. This is called intercostal retraction. Bluish nails or lips may signal lack of sufficient oxygen to the tissues due to severe asthma. The extreme respiratory difficulty can also cause the neck muscles to work harder. She may notice a very fast heartbeat.

The official diagnosis of asthma requires 3 things. First, episodes of symptoms suggesting blockage of air-flow (airflow obstruction) must be present. The obstruction must be at least partly reversible (it can respond to medication), and other explanations for the symptoms must be ruled out (2).

There is an asthma screening program occurring in convenient locations, such as malls and health fairs, that is carried out by the Nationwide Asthma Screening Program. More information on screening dates and locations is available (14).

Epidemiology: Who Gets Asthma? Is Asthma Different In Men and Women?

Among 5-24 year-olds, the risk of dying from asthma in 1993 was 1.5 times higher in men than women (2). Mortality from asthma in females in 1995 was 2.5 per 100,000, compared to 1.9 in males. 1998 American Lung Association estimates observed that asthma increased much faster in women than men, 42% vs. 81%, between 1982 and 1994.

In people aged 20-50, the ratio of women to men admitted to the hospital for asthma is 3:1 (2). In 1995, the rate of hospitalization for asthma in females was 22.4 per 10,000, vs. 16.5 in men (2). Women also had longer lengths of stay once admitted to the hospital, 4.1 vs. 3.2 days (2). It is thought that asthma may therefore be related to hormonal conditions. There is some research proof of this.

Asthma is more severe in women, especially in the childbearing years, than in men, and it may get worse during a woman's menstrual period, again suggesting a possible involvement of female hormones. Although asthma affects females more than males in general, during childhood the opposite is true (2).

In 1995, 52.6 women per 1000 population had asthma, compared to 52.6 in men (2). Females also have a greater use of emergency rooms for asthma, 82.3 vs. 57.8 per 10,000 in men vs. women in 1995 (2). These gender differences appear to be growing, not lessening.

Preliminary work suggests that woman may access outpatient care for asthma more frequently than do men, and that women in the emergency room for asthma may have a bigger chance of being admitted to the hospital compared to men. Also, of asthma patients admitted to the intensive care unit, females may have worse asthma (more severe disease) than do males. The reasons for these gender differences in asthma are not yet known. Since it has been reported that women use "rescue medications" (see treatment section below for description) more frequently than men do, the women may either have more severe asthma, may not be prescribed the daily maintenance medications as often as are men or may not be taking their controller medication.


Rarely, asthma can result in death. Asthma causes 5000 deaths per year (6). The asthma deaths occur mostly in blacks aged 15-24 years (2). It causes days of restricted activity and multiple hospitalizations each year.

Prognosis: How is Asthma Different in Pregnancy?

All women are different. The course that asthma will take when an asthmatic woman becomes pregnant is impossible to predict beforehand. Furthermore, there is research evidence suggesting that women with asthma are higher risk of having pre-term infants, low birth-weight infants, infants small for their gestational age, increased hospital stays, and other complications. There is strong medical basis to believe that the risk of using asthma medication in pregnancy is minuscule compared to the risk of NOT treating the asthma.

Prevention of Asthma and Asthma Attacks

Something Usually Triggers an Asthma Attack

An asthma attack occurs when the airways narrow (the process called bronchoconstriction) and inflamed, usually as a result of an asthma trigger. Obviously, if a woman knows certain things trigger her asthma, she should try to avoid exposure to them whenever possible. Usually, something is responsible for triggering asthma flares. The following are issues regarding asthma triggers and prevention of asthma symptoms.

In terms of asthma in children, research is growing daily that strongly suggest that if we abolished exposure of children to cigarette smoking we could actually prevent some cases of asthma. Exposure to cigarette smoke is a risk factor for asthma. Pregnant asthmatics should avoid not only smoking but also exposure to side-stream tobacco smoke.

In families with strong atopic (asthma, allergic eczema rashes, hay fever) tendencies, it is recommended that the infant be fed exclusively with breastmilk as opposed to formula, to decrease the infants risk of getting allergic food sensitivities. Smoking is a well-known asthma attack trigger. Smoking (even just being around someone who is smoking), feathers, mold, and cold air are frequent culprits that should be avoided if possible.

Unfortunately, respiratory viruses are very common triggers of asthma and are often not preventable. It is a good idea to avoid people with known respiratory infections. Influenza vaccination is recommended for asthmatics who will be in the second and third trimesters of pregnancy at the time of annual influenza seasons. Rhinitis (hay fever, reaction to trees and grasses), sinusitis, and gastroesophageal reflux (irritation of the esophagus caused by the gastric contents, see above) can also contribute to asthma.

Respiratory reactions to food can occur when people do not recognize that their trigger food is hidden in the food they are eating. Smoke from food cooking, or a wood-burning fireplace, can also trigger an asthma attack.

Exercise can cause bronchoconstriction in about 70% of asthmatics. This is thought to be partly because exercise prevents the nose from warming and humidifying the air, since mouth-breathing is common during exercise. However, a physician's role is to instruct a woman on how to use appropriate treatments so that she will be able to exercise without having the asthma stop her from achieving her desired activity level. There is medication available to use right before exercise to help prevent exercise-induced symptoms. Changes in the weather can trigger asthma. Dry cold air may be especially bothersome.

Strong smells or sprays can trigger asthma and should be avoided when possible. These things can irritate people without asthma, but people with asthma are even more sensitive to them. Soaps or shampoos also often contain perfume and should be avoided.

A recent report from the Nurses' Health Study found that increasing weight (as adjusted for height) was associated with increasing risk of asthma in women. The study also found that weight gain after age 18 was strongly associated with risk of adult-onset asthma.

Some people's asthma is triggered by aspirin, though these people represent a very small portion of asthmatics overall. A physician can help determine which particular asthma patients are at risk for aspirin-induced asthma.

Avoiding triggers may help both in averting the acute asthma attack and also over time in improving asthma control.

Treatment Overview

Asthma can be controlled. It requires good communication with a treating physician. There is no reason to settle for lack of improvement in asthma symptoms. Taking care of asthma means carrying out both environmental and medication plans. An asthma episode can often be halted if treated early with medication. People who do not realize or believe that are at risk of dying from asthma. Research confirms that in the community, asthma patients usually have a good prognosis in other words that they have similar survival compared to people in the community without asthma.

Many of the hospitalizations and deaths resulting from asthma can be prevented, but only if people: recognize the symptoms, act on symptoms quickly, avoid asthma triggers, take the correct medications regularly and in correct fashion, and get good education regarding asthma and asthma medications. Some ways to accomplish these goals are discussed below.

Non Pharmacologic (Non-Medication) Intervention

Dust can have mold, animal dander, and dust mites in it. The dust mite is a tiny creature that lives in bedding and furniture as well as carpet. Dust mites are more plentiful in the summer and have trouble surviving in the winter. Dust mite waste products are the cause of allergic reactions. Although dust may cause inflammation in most people, in asthmatics it can cause bronchial constriction (narrow of the airways) and hyper-responsiveness (excessive "twitchiness" of the airways, tendency of the airways to spasm). It is recommended that people susceptible to asthma attempt to eliminate dust sources. Methods to do this include eliminating carpeting, covering mattresses and pillows with special allergy covers (plastic with a zipper, available in many major linen store chains), and washing bedding frequently in hot water. Hot temperatures are necessary for killing the dust mites. Feathers and down are probably not wise to have around asthmatics, nor is wool. As much as possible furniture should be minimal and not upholstered, and dust-prone venetian blinds should be restricted. Curtains should be washed weekly in hot water. Use of pillows or mattresses made of straw is not recommended. Extra throw rugs and old moldy dusty stuffed animals or throw pillows should probably be removed. The best toys are probably those made of washable materials that are not likely to hold dust. Wood is a good toy material from the asthma standpoint.

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Although open windows can allow pollens and other triggers into the house, there may be a trigger in the house, such as smoke, that necessitates opening a window.

Pets with fur should be kept out of the bedroom. If pets are to be kept in the household, they should be bathed twice weekly to reduce the amount of allergens (substances with potential to cause asthma or allergy symptoms). An asthmatic may be allergic not only to the animal itself but also to danders or pollens that the pet carries in from the outside.

Following these recommendations down the last detail would be unrealistic, of course, but at least they are guidelines. Additionally, perhaps some of the chores that are associated with asthma triggers can be done when the person with asthma is out of the house.

Although these recommendations have not been proven to be totally effective (indeed some research finds these measures to not be helpful at all), they are inexpensive and without side effects compared to medications, and therefore are considered standard measures for consideration by every asthma. Physicians generally counsel all asthmatic patients regarding these measures, if they are found to be allergic by skin or blood testing.

Do Filters Help?

High-energy particulate absorption (HEPA) filters have recently gained in popularity. They are filters that remove many allergens from the air. There is not complete proof that these filters should be used by everyone with asthma.

Treatment With Medication: General Considerations

Key point: The risk of asthma that is not controlled in pregnancy is greater than the risk of using medication! The baby needs oxygen!

There are several kinds of asthma medications. Generally, they come in two categories: fast-acting medication (called rescue medication, used for immediate relief of symptoms) and medication (maintenance therapy) that is used regularly each day to prevent the need for the rescue medication. Preventive asthma medications are not addictive, even when used for years!

People who really know how to use their asthma medications and how to alter them with changes in their asthma symptoms not only feel better about their asthma, but research is also beginning to prove that they also have more healthy days than people who just visit the doctor at regular intervals.

Allergy shots (Immunotherapy) is effective for most people with hayfever. It clearly also helps some people with asthma as well. Those asthmatics likely to respond are children, highly allergic individuals and those with poorly controlled hayfever or sinusitis.

The latest treatment recommendations are based on the National Asthma Education and Prevention Program's Report of the Second Expert Panel on the Guidelines for the Diagnosis and Management of Asthma, published in 1997 (2). These treatment guidelines, sponsored by the National Heart, Lung, and Blood Institute, give more emphasis to the use of anti-inflammatory medications, and to possible prevention of asthma, than did prior guidelines. The plan is called a "step approach". This means that if one medication does not do the job, the dose or frequency of doses is raised and other medication is added, and then as the asthma is better controlled, the medications are decreased in a "step down". The 2 generally categories of medication are controller medications (maintenance medications) and reliever medications (rescue medications).

A. Rescue Medication: Inhaled for Quick Relief

For acute, meaning immediate, relief, medication that dilates (opens) the airways is used. These medications, b-agonists, are usually taken in inhaled forms, called metered dose inhalers (MDI's). Examples include albuterol and metaproterenol. There are few side effects of these inhaled bronchodilator medications. Some people may get palpitations, a sense of the heart beating fast, or a sense of feeling "jittery". Some people seem to be more sensitive to those side effects than others. Some people may notice this type of side effect only occur at high doses of the medications. This quick relief medicine should always be carried in case of unexpected need. Often people will be told to keep these medications scattered in easy-to-find locations, like purses or pockets, desk at work, or glove compartment.

B. Maintenance Therapy: Inhaled for Long-Term Control

Because asthma's underlying cause is thought to be inflammation (swelling in the airways), anti-inflammatory therapy is the basis for prevention of acute attacks (exacerbations). Daily preventive (maintenance) medication may be needed if people cough, wheeze, or have chest tightness more than once weekly, if night-time asthma wakes them up, if they have many asthma attacks, or if they are using asthma rescue medication daily.

Therapy consists of inhaled corticosteroids. Corticosteroids are drugs that if taken orally can have significant side effects over the long-term, although these are not the same drugs that became popular with body-builders. Therefore, inhaled forms of the corticosteroids were developed in the form of MDI's. Examples include fluticasone, beclomethasone, and budesonide. Although it is known which of these is the most potent compared to the others (fluticasone), studies actually comparing use of the medications are not very numerous. Steroids are anti-inflammatory, so that they decrease airway swelling, lessen mucus, and decrease the overly active "twitchy" problem in the airways.

There are no immediate side effects of steroid MDI's that a person would feel. Thrush, a whitish yeast infection on the tongue, can occur as a side effect, and is minimized by rinsing out the mouth with water after use and using a "spacer" device that attaches to the inhaler. Spacers are available by prescription and help the medication get into the lungs instead of depositing in the mouth. Based on the fact that use of oral steroids can put people at risk of osteoporosis (brittle bones), there is some concern that inhaled steroids might also decrease bone density, and as a consequence cause fractures later on. The research so far is regarding this possible side effect is controversial, but suggests that this possible side effect is greater with higher potency or higher doses of inhaled steroids. Hopefully the exact degree of risk with different preparations and doses will become clearer in the future. For the time being, consulting with a physician that adequate calcium intake, vitamin D intake, and exercise are being achieved for bone health is a wise idea.

The safest and most effective asthma treatment is inhaled medication, including corticosteroids

Salmeterol is a relatively new medication that is a longer-acting b-agonist. It is often used in people frequently needing b-agonists, in hopes of decreasing the need for short-acting rescue medications. It is also sometimes added to inhaled corticosteroids to improve asthma control or to reduce the dosage of these inhaled corticosteroids needed for asthma control. Some research has shown that asthma control in people already using steroid MDI's is improved moreso by addition of salmeterol than by raising the dose of the steroid MDI. Of course, this means using two inhalers instead of one inhaler. Salmeterol is sometimes used as a long-term medication to prevent exercise-induced asthma, but there is some research showing that its effectiveness when used for this specific reason may slightly decrease gradually with time.

Cromolyn is a medication that has been around for a long time. It is one of the safest medications of all available prescription medications, but it is not very potent. It is used sometimes as maintenance therapy to prevent acute asthma attacks, but it does not help during an acute attack.

C. Maintenance Therapy: Oral (by mouth) for Long-Term Control

Theophylline is an older asthma medication that is taken in pill-form. It acts as a bronchodilator and seems to be especially helpful for people with night-time decrease in lung function that commonly occurs in people with asthma. It's use at night has largely been replace by the long- acting bronchodilator salmeterol.

Use of theophylline requires blood tests to determine blood levels of the medication as part of its safety monitoring. It also has potential side effects, including nausea, increased heart rate (experienced as palpitations), irritability, and insomnia, among others. These side effects are similar to those of caffeine. It also has potential for many drug interactions, meaning it can affect the use of other medicines used at the same time for other conditions, and vice-versa. Acute illnesses can also alter its metabolism (how the drug acts in the body and is eliminated from the body). For these reasons it is infrequently used in asthma treatment. Newer medications particularly inhalers like salmeterol are more effective and have less side effects.

A new class of maintenance medicines has emerged in the last several years. In fact, they were the first new treatment to be approved in 20 years for chronic asthma They are pills that act to reduce the production of, or the action of, chemicals that the body itself makes during an asthma attack. These chemicals called leukotrienes are produced by the inflamed airway, and narrow the airways. These medications are called anti-leukotrienes. Depending on the medication, they either stop the production of the trouble-making leukotrienes, or else block the harmful action of the leukotrienes. It is hoped that they can reduce the need for, or possibly the dose of, other asthma medications. These medications include zafirlukast, montelukast, and zileuton. These antileukotriene drugs directly block bronchoconstriction but are also anti-inflammatory, whereas corticosteroids are only anti-inflammatory. These medications have not been compared to each other, so it is not known if one has any clear advantage over the others. Most of the benefit of these drugs is seen within 2-4 weeks of starting the medication (A), and they generally reduce the need for rescue therapy by 1/3rd (A). They help decrease nighttime asthma symptoms as well (A).

When compared head-to-head, the anti-leukotrienes and the inhaled steroids each help certain lung function tests, quality of life, night-time awakenings, numbers of asthma-control days, and asthma attacks. The two medications were each helpful as controller medications for chronic asthma. Both drugs were very well tolerated in terms of side effects. Other research has added anti-leukotrienes to high doses of inhaled steroids in chronic asthma patients. Patients who did have the anti-leukotriene added had a better chance of successfully reducing the inhaled steroid dose than those who did not add an anti-leukotriene to their inhaled corticosteroids. The anti-leukotrienes are not yet felt to be useful in severe asthma, and many people with milder asthma are already controlled and happy on either intermittent rescue medication or chronic inhaled corticosteroid MDI's with only occasional need for rescue medication.

It might be that these medications if used regularly for many weeks, are good at preventing exercise-induced asthma, as is being shown in recent research, and that they may help a certain type of asthma called aspirin-sensitive asthma. However, there are many issues that have come up regarding these medications; people may find using MDI's more convenient that taking these pills, MDI's in low doses have minimal absorption compared to pills thus possibly less potential for side effects, and long-term studies of these pills are not available yet. Also, zileuton has potential to cause abnormal liver function test in the blood, so that all people taking this medication will need liver test monitoring via blood tests at intervals, especially in the first 3 months of use. Therefore their precise role is still being determined, especially in the long-term. Specifically, we need long-term safety and effectiveness data, and need to clearly establish what specific group of asthmatics will benefit most from them. Probably for the time being, in real daily practice while we await research, their use is considered in the following mild to moderate asthmatics: those with less than optimal benefit from inhaled steroid, those with aspirin-sensitive asthma, and those needing high doses of inhaled or oral steroids.

In summary, then, these anti-leukotrienes are a good choice for people with aspirin-induced asthma, and they can improve lung function in those with chronic asthma by decreasing: need for rescue medications, asthma symptoms, frequency of attacks needing oral steroid pills, and dose of inhaled steroids needed for long-term control. They are also useful for exercise-induced asthma.

In very severe asthma, daily oral corticosteroids (or steroids) may be necessary. These have many potential side effects, so that physicians generally explore every single other reasonable alternative before starting oral corticosteroids. They also try to use other medications to reduce the necessary dose of these steroid pills. These oral steroids are not the same medications used (abused) by body builders. They can be life-saving drugs for people with severe asthma, and they are used in the lowest dose possible in order to reduce possible side effects. When people are admitted to the hospital having an acute asthma attack that cannot be terminated with inhaled medications, they are often given corticosteroids in intravenous form (into the veins in their arms) for a short time to bring the attack under control, after which the medication is converted back to oral and inhaled forms. The most frequent use for oral steroids is a short course (5-10 days). This is the most effective way to control acute asthma attacks or poorly controlled chronic asthma which are not responding to inhaled medications.

The Office of Women's Health of the Federal Drug Administration has a section called Women's Health: Take Time to Care (7), the aim of which is to make women aware of safe medication use. Women are the principal users of medications and who often have to administer medication to family members.

D. Use of Medications: Optimizing Their Effects and Safety

Frequent review of the technique of using inhaled medications is very helpful. First, the cap should be removed. The inhaler should be shaken before use. Inhalation of the medication should be done with the head tilted back, with the mouth about 1 inch away from the inhaler. Before inhaling the medication, patients should exhale (breathe out) completely. The medication is inhaled slowly, over 3 to 5 seconds. Then breath should be held for 10 seconds so the medication will get to and stay in the lungs. When prescribed two puffs at one time, a few seconds should go by between puffs. People having difficulty using the inhaler with a spacer (see below) should discuss the problem with their physician. The inhaler and its cap should be cleaned in warm water each day. The mouthpiece should also be washed occasionally with mild dishwashing detergent and water. After being washed each time, the parts should be allowed to dry before storage.

Spacers are devices used to increase the amount of medicine actually reaching the lungs. They also help to avoid the thrush (see above) that can happen as a side effect of the inhaled corticosteroids. Rinsing out the mouth after each use of inhaled corticosteroids will also help minimize thrush. The spacer can minimize the amount of medication that just stays on the tongue, so that the medicine will go where it belongs, in the lungs. The spacer holds the medicine so it can be inhaled slowly, and helps to minimize cough that results occasionally from using an MDI.

If a woman uses her quick-relief (rescue) medication more than 3 times weekly, chances are she should be on a daily long-term therapy medication to decrease inflammation over the long-term. Using inhaled steroids early in asthma's course may not only control asthma better but also make lung function normal.

People who use both inhaled steroids and rescue inhaled bronchodilators should first use the bronchodilator to open the airways, to better allow the corticosteroid that they use next to reach the lungs.

All women with asthma need to have education regarding what to expect from their asthma as well as what to expect from their asthma medications. Education is critical, and every woman's plan is individualized so that a woman should be able to do her usual activities. Women should expect or request a written plan from a treating physician which includes expected length of treatment with each medication, when to expect each medication's effect to be felt, and what to do if a dose is missed.

To see how much medication is left in an MDI canister can be difficult. However, putting it in a sink full of water can give an idea of how empty the canister is. A canister floated in this way will float completely to the top when it is empty and sink all the way to the bottom when full. It will be floating vertically when half full, and sink vertically when mostly full.

The older form of the inhaled asthma medications is slowly being phased out. This is because the older MDI's have chlorofluorocarbons (CFC's). These CFC's decrease the amount of ozone in the ozone layer around the earth and are therefore thought to have a harmful effect on the environment. Therefore, the medications are gradually being put into forms that do not contain CFC's. Some of these forms are already available. New formulas, such as dry powder inhalers, are being substituted for the older CFC MDI medications, with the goal of one day having only non-CFC-containing inhalers.

Further information on how to use inhalers probably and regarding monitoring and treatment of asthma are available from the NHLBI (2).

E. Treatment & Monitoring Based on the Type of Asthma

Doctors usually give out a written set of instructions that describes the individual treatment plan. The partner in the treatment plan, the woman with asthma is expected to keep an accurate diary of her symptoms. She needs to go the doctor at least a few times a year, even if she feels okay and thinks her asthma is doing fine.

Also, if she has moderate or severe persistent asthma, or if she ever develops severe asthma attacks regardless of the type of asthma she has, she should monitor her peak expiratory flow, sometimes called simply peak flow. The highest of 3 trials using a peak flow meter is the person's peak flow. Peak flow monitoring helps both the woman and the physician know how her asthma is really doing, and may help the woman be more aware of how her symptoms relate to her lung function at any given time. The NIH has information on performing peak flow monitoring. (2)

Technically speaking, asthma is no longer defined as mild, moderate, or severe. Instead, more specific categories are now used, and doctors base their treatments on them. Asthma classification categories are now mild intermittent, mild persistent, moderate persistent, and severe persistent. Within each one of these categories, attacks can be mild, moderate, or severe.

Summary of Treatment Issues Specific to Asthma and Pregnancy

Asthma course can get better, worsen, or stay the same during pregnancy, in unpredictable fashion. Risk of using asthma medications during pregnancy is much lower than the risk of bad outcomes due to uncontrolled asthma. Oxygen supply for the fetus relies on proper control of a pregnant woman's asthma. Asthma is to be treated as aggressively in pregnant as in nonpregnant women, with both rescue and preventive medications. Although women are understandably worried about using any medications during pregnancy, use of asthma medications during pregnancy clearly bring about less in the way of bad outcomes than does leaving asthma uncontrolled during pregnancy.

References, and for further information or help, Government initiatives and national organizations devoted to asthma.

(1) The Global Initiative for Asthma is a project of the National Heart, Lung, and Blood Institute, National Institutes of Health, and the World Health Organization. Its purpose is to increase public awareness of asthma, support asthma research, decrease its harmful toll on the U.S., and improve its management. Information is at

(2) National Heart, Lung, and Blood Institute is at, and their specific asthma information for the public is at, 1-301-251-1222

(3) The National Institute of Allergy and Infectious Diseases of the National Institutes of Health

(4) The U.S. Environmental Protection Agency is at 800-438-4318,

(5) The National Institute for Occupational Safety and Health (NIOSH) is at

(6) The American Lung Association is at 1-800-LUNG-USA,

(7) The American Academy of Allergy Asthma & Immunology is at, 1-800-822-2762

(8) The Office of Women's Health of the Federal Drug Administration has a section called Women's Health: Take Time to Care, at

(9) En espanol (in Spanish):

(10) The Asthma and Allergy Foundation of America is at, 1-800-727-8642

(11) The National Jewish Medical and Research Center is at, and its information service is at 1-800-222-LUNG

(12) The American Thoracic Society is at

(13) The American College of Chest Physicians is at

(14) The Allergy, Asthma & Immunology Online (from American College of Allergy, Asthma & Immunology) is at

(15) The Mayo Clinic Health Oasis Allergy & Asthma Center is at

(16) The National Asthma Education and Prevention Program (NAEPP) is at /naepp/naep_pd.htm, 1-301-251-1222

(17) The American College of Allergy, Asthma, and Immunology 1-800-842-7777


(A) Drazen et al, Treatment of asthma with drugs modifying the leukotriene pathway, NEJM, 340(3):197-206.