Introduction:

Asthma is a chronic disease that involves inflammation of the lungs. Airways swell and restrict airflow in and out of the lungs, making it hard to breathe. The word asthma comes from the Greek word for "panting." People with asthma pant and wheeze because they can' t get enough air into their lungs.

Normally, when you breathe in something irritating or you do something that causes you to need more air, like exercise, your airways relax and open. But with asthma, muscles in the airways tighten, and the lining of the air passages swells.

About 20 million Americans have asthma, including 9 million children. In fact, asthma is the most common chronic childhood illness. About half of all cases develop before the age of 10, and many children with asthma also have allergies.

Asthma can either be allergic or non-allergic. In allergic asthma, an allergic reaction to an inhaled irritant -- pet dander, pollen, dust mites -- triggers an attack. The immune system springs into action, but instead of helping, it causes inflammation. This is the most common form of asthma.

Non-allergic asthma does not involve the immune system. Attacks can be triggered by stress, anxiety, cold air, smoke, or a virus. Some people have symptoms only when they exercise, a condition known as exercise-induced asthma.

While there is no cure for asthma, it can be controlled. People with moderate to severe asthma should use conventional medications to help control symptoms. Complementary and alternative therapies, used under your doctor' s supervision, may help, but shouldn' t replace conventional treatment.

Signs and Symptoms:

Most people with asthma may go for periods of time without any symptoms, then have an asthma attack. Some people have chronic shortness of breath that gets worse during an attack. Asthma attacks can last minutes to days, and can become dangerous if airflow to the lungs becomes severely restricted.

Primary symptoms include:

• Shortness of breath
• Wheezing -- usually begins suddenly; may be worse at night or early in the morning; can be made worse by cold air, exercise, and heartburn; is relieved by using bronchodilators (drugs that open the airways; see Medications)
• Chest tightness
• Cough (dry or with sputum) -- in cough-variant asthma, this may be the only symptom

If you have any of these symptoms, seek emergency treatment:

• Extreme difficulty breathing or stopping breathing
• Bluish color to the lips and face, called cyanosis
• Severe anxiety
• Rapid pulse
• Excessive sweating
• Decreased level of consciousness, such as drowsiness or confusion

Causes:

Asthma is most likely caused by several factors. Genes play a part; you' re more likely to develop asthma if others in your family have it. Among those who are susceptible, being exposed to environmental factors such as allergens, substances that cause an allergic reaction, or infections may increase the chance of developing asthma.

Risk Factors:

The following factors may increase the risk of developing asthma:

• Having allergies
• Family history of asthma or allergies
• Being exposed to secondhand smoke
• Having upper respiratory infections as an infant
• Living in a large city
• Gender -- among younger children, asthma develops twice as often in boys as in girls, but after puberty it may be more common in girls
• Obesity
• Gastroesophageal reflux (heartburn)

Triggers

Childhood asthma, in particular, can be triggered by almost all of the same things that trigger allergies, such as:

• Dust, cockroach waste, pet dander, indoor and outdoor mold, pollen
• Air pollutants, such as smoke, perfumes, diesel particles, sulfur dioxide, high ozone levels, and fumes from paint, cleaning products, and gas stoves
• Changes in the weather, especially in temperature (particularly cold) and humidity

Other triggers include:

• Activities that affect breathing, such as exercising, laughing, crying, yelling
• Stress and anxiety

Diagnosis:

Asthma symptoms can mimic several other conditions, and your doctor will take a thorough history to rule out other diseases. You may also have lung function tests to measure how much air your lungs can hold and how much air you breathe out. Your doctor may use a spirometer to measure how much air you exhale and how quickly you get air out of your lungs. Other tests may include chest and sinus x-rays, blood tests, or allergy tests.

Asthma is classified as:

• Mild intermittent: Having mild symptoms up to 2 days a week and 2 nights a month
• Mild persistent: Having symptoms more than 2 a week but not more than one time in a single day
• Moderate persistent: Having symptoms once a day and more than one night per week
• Severe persistent: Having symptoms throughout the day on most days and often at night.

Prevention:

Although you can' t prevent asthma, you can take steps to reduce the number and frequency of attacks:

• Avoid allergens and irritants as much as possible. For example, reduce your exposure to dust mites by using special mattress and pillow covers that keep allergens out and removing carpets from bedrooms. Clean your house frequently. Wearing a mask while cleaning and choosing cleaners without harsh chemicals may help.
• Exercise. Even people with exercise-induced asthma can stay active, and exercise will help you by strengthening your lungs and helping you maintain a proper weight. Taking precautions when it' s cold outside -- such as wearing a face mask to warm the air that you' re breathing -- can help you avoid asthma symptoms. Talk to your doctor before starting an exercise regimen.
• Pay attention to your breathing. Watch for signs of an oncoming attack, such as wheezing. Your doctor may give you a machine called a peak flow meter that can detect slight differences in your breathing before you even notice them, so that you can take medication to ward off an attack. Your doctor will help you know which changes would mean you need medical attention right away.
• Treat attacks quickly. The sooner you treat an attack, the less severe it will be, and the less medication you' ll need.
• If you have allergies, immunotherapy ("allergy shots") may lower the number of asthma attacks and their intensity, and reduce the amount of medication you need. Immunotherapy includes regular injections of the substance you're allergic to, with each shot containing a slightly higher amount. Sublingual immunotherapy delivers the allergen in drops under the tongue. Over time your immune system becomes used to the allergen and no longer reacts to it. Talk to your doctor about whether immunotherapy is right for you.

Treatment:

Avoiding asthma attacks, reducing inflammation, and preventing lung damage are the primary goals of treatment. The more you know about your condition, the more closely you can work with your doctor to develop an asthma action plan. To control asthma, you need to prevent exposure to allergic triggers and take medication as prescribed. You may need emergency medications during an asthma attack, but monitoring your breathing and taking your medications every day will help you control asthma over the long term.

In a severe attack, you may need to be hospitalized for oxygen and medications that are given intravenously (IV).

Lifestyle

• If you smoke, quit.
• Lose weight if you are overweight. Being overweight may put pressure on the lungs and trigger an inflammatory response.
• Monitor your condition every day using a peak flow meter, a portable device that helps measure how your lungs are working. Keep a diary of readings to show your doctor. Together, you will establish your "personal best" reading. You should call your doctor if your peak flow reading falls below 80% of your personal best and go to the hospital if it falls below 50%.
• Keep a journal that logs changes or attacks -- it may help determine triggers.

Medications

Medications for asthma are prescribed for two different purposes: to stop an immediate attack, and to control inflammation and reduce lung damage over the long term.

Quick relief medications -- These drugs are called bronchodilators and help open the airways when you have an attack.

Short-acting beta-adrenergic agonists start working immediately. These drugs include:

• Albuterol (Proventil)
• Metaproterenol (Alupent)
• Pirbuterol (Maxair)
• Terbutaline (Brethaire)
• Levalbuterol (Xopenex)

Sometimes, steroids are needed for an acute asthma attack. They can take longer to work (from a couple of hours to a few days) and include:

• Prednisone
• Prednisolone
• Methylprednisolone
• Hydrocortisone

Long-term control -- These drugs are usually taken every day.

Inhaled corticosteroids reduce inflammation and have fewer side effects than oral corticosteroids. They include:

• Beclamethasone (Qvar)
• Budesonide (Pulmicort)
• Flunisolide (Aerobid)
• Fluticasone (Flovent)
• Triamcinolone (Azmacort)

A class of drugs called leukotriene modifiers help reduce the production of inflammatory chemicals called leukotrienes that cause your airways to swell. They include:

• Montelukast (Singulair)
• Zafirlukast (Accolate)

Cromolyn (Intal), Nedocromil (Tilade) -- These medications, which are inhaled, can help prevent mild to moderate attacks and are used to treat exercise-induced asthma.

Theophylline (TheoDur) -- This medication helps open airways and prevent asthma symptoms, especially at night. Too much can cause serious side effects, so your doctor will monitor levels in your blood.

Omalizumab (Xolair) -- Used to treat allergic asthma when other medications haven't worked.

Nutrition and Dietary Supplements

Although there is no diet for asthma, people who have allergic asthma may also have food allergies that can make their asthma worse. If you think you may have food allergies, talk to your doctor about trying an elimination diet.

Eating plenty of fruits and vegetables that are high in antioxidants may also help you keep your asthma under better control. One study found that people with asthma who followed the Mediterranean diet had better control of asthma symptoms. Some studies have shown that people with asthma tend to have low levels of certain nutrients, but there is no evidence that taking supplements helps reduce asthma attacks. However, an overall healthy diet will help you get the nutrients you need and help your body deal with a long-term condition such as asthma.

• Choline -- This B vitamin may help reduce the severity and frequency of asthma attacks. Some evidence indicates that higher doses (3 g per day for adults) may work better, but you should not take high doses without your doctor's supervision. More research is needed to say for sure whether choline helps.
• Magnesium -- The idea of using magnesium to treat asthma comes from the fact that people who have asthma often have low levels of magnesium, and from some (but not all) studies showing that intravenous (IV) magnesium can work as an emergency treatment for an asthma attack. However, studies that have looked at whether taking oral magnesium helped have shown mixed results. More research is needed.
• Fish oil -- The evidence for using omega-3 fatty acids (found in fish oil) to treat asthma is mixed. At least a few studies have found that fish oil supplements may reduce inflammation and symptoms in children and adults with asthma. But the studies have only included a small number of people, and one study found that fish oil might make aspirin-induced asthma worse. Ask your doctor whether a high quality fish oil supplement makes sense for you. In high doses, fish oil may increase the risk of bleeding, especially if you take a blood thinner such as warfarin (Coumadin).
• Quercetin -- Quercetin, a kind of antioxidant called a flavonoid, helps to reduce the release of histamine and other allergic or inflammatory chemicals in the body. Histamine contributes to allergy symptoms such as a runny nose, watery eyes, and hives. Because of that, quercetin has been proposed as a treatment for asthma. But no human studies have examined whether it works or not. Quercetin can interact with certain medications, so ask your doctor before taking it.
• Vitamin C (1 g per day) -- One preliminary study suggested that children with asthma had significantly less wheezing when they ate a diet rich in fruits with vitamin C. Vitamin C does have anti-inflammatory and antioxidant properties, which may help you maintain good health overall. Some studies have indicated that taking a vitamin C supplement (1 g per day) may help keep airways open, but other studies have found no benefit.
• Other -- Other supplements that may help treat asthma include:
• Coenzyme Q 10 (CoQ10) -- if you have asthma, you may have low levels of this antioxidant in your blood. Researchers don't know, however, whether taking CoQ10 supplements will make any difference in your symptoms.
• Lycopene and beta-carotene -- preliminary data suggests that these two antioxidants, found in many fruits and vegetables, may help prevent exercise-induced asthma. People who smoke or take simvastatin (Zocor) should not take beta-carotene without talking to their doctor.
• Vitamin B6 -- may be needed if you are taking theophylline because this medication can lower blood levels of B6.
• Potassium -- levels in the body also may be lowered if you take theophylline.

Herbs

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, under the supervision of a health care practitioner.

• Boswellia (Boswellia serrata, 3 mg three times per day) -- Boswellia (also known as Salai guggal) is an herb commonly used in Ayurvedic medicine, a traditional Indian system of health care. In one double-blind, placebo-controlled study, people who took boswellia had fewer attacks and improved lung function. Boswellia may help leukotreine modifiers work better. However, more research is needed. People who take medication to lower their cholesterol, or people who take nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin) should talk to their doctor before taking boswellia.
• Coleus forskohlii -- Coleus forskohlii, for forskolin, is another herb used in Ayurvedic medicine to treat asthma. A few preliminary studies suggest that inhaled forskolin powder seemed to relieve symptoms, but more research is needed to know for sure. People who have diabetes or thyroid conditions should not take forskolin. If you take blood thinners such as warfarin (Coumadin), taking forskolin may increase your risk of bleeding. Pregnant women should not take forskolin. Forskolin interacts with calcium channel blockers such as verapamil (Calan, Verelan), nifedipine (Procardia), and diltiazem (Cardizem, Dilacor) and with nitroglycerin (Nitro-Bid, Nitro-Dur, and Nitrostat) and isosorbide (Imdur, Isordil, and Sorbitrate).
• Tylophora (Tylophora indica, 250 mg one to three times per day) -- Tylophora has also been used historically to treat asthma. Some modern scientific studies show that it can help reduce symptoms, but the studies were of poor quality. More research is needed. Tylophora may cause serious side effects at high doses, so talk to your doctor before taking it. Do not take tylophora if you are pregnant, have diabetes, high blood pressure, or congestive heart failure.
• Pycnogenol (Pinus pinaster, 1 mg per pound of body weight, up to 200 mg) -- A 2002 review of studies on a standardized extract from French maritime pine bark, called pycnogenol, suggests that it may reduce symptoms and improve lung function in people with asthma. Another study found that children with asthma who took pycnogenol along with prescription asthma medications had fewer symptoms and needed fewer rescue medications. Do not use pycnogenol if you have diabetes or take medication for high blood pressure. If you take blood thinners such as warfarin (Coumadin) or aspirin, taking pycnogenol may increase your risk of bleeding.
• Saiboku-to -- In three preliminary studies, a traditional Japanese herbal mixture called Saiboku-to has helped reduce symptoms and allowed study participants to reduce doses of corticosteroids. In test tubes, Saiboku-to has shown anti-inflammatory effects. Saiboku-to contains several herbs, including Asian ginseng (Panax ginseng), Chinese skullcap (Baikal scutellaria), licorice (Glycyrrhiza glabra), and ginger (Zingiber officinale). These herbs can interact with other medications, so talk to your healthcare provider before taking Saiboku-to.

Acupuncture

Some preliminary studies indicate that acupuncture may help reduce symptoms for some people with asthma, but not all studies agree. Acupuncture should be used in addition to, not as a replacement for, conventional medicine when treating asthma.

Homeopathy

Although very few studies have examined the effectiveness of specific homeopathic therapies, professional homeopaths may consider the following remedies for the treatment of asthma based on their knowledge and experience. Before prescribing a remedy, homeopaths take into account a person's constitutional type-- your physical, emotional, and psychological makeup. An experienced homeopath assesses all of these factors when determining the most appropriate treatment for each individual.

Some people may find their symptoms get worse for a short time when starting on a homeopathic remedy. Because this may be dangerous for some people, be sure to work with a knowledgeable homeopath.

• Arsenicum album -- for asthma that generally worsens between midnight and 2 am and is accompanied by restlessness, anxiety, chills, and thirst.
• Ipecacuanha -- for those with asthma, particularly children, who have significant tightness in the chest, a chronic cough with lots of phlegm that may lead to vomiting, and worsening of symptoms in hot, humid weather.
• Pulsatilla -- for asthma with yellow or greenish phlegm that gets worse in the evening, in warm, stuffy rooms, or after consuming rich, fatty foods; this remedy is most appropriate for adults or children who are tearful and clingy or sweet and affectionate.
• Sambucus -- for asthma that awakens a person at night with a sensation of suffocation; symptoms worsen when the person is lying down .

Mind-Body Medicine

Because stress and anxiety can make asthma worse, including stress management techniques in your daily life may help reduce symptoms. These techniques do not directly treat asthma, however.

• Hypnosis -- may be especially useful for children, who can easily learn the technique.
• Yoga -- in addition to general relaxation and stress reduction, several studies of people with asthma have suggested that lung function improves with the regular practice of yoga. Any benefits in breathing appear to be slight, however.
• Journaling -- A study published in the New England Journal of Medicine documented the positive effect of daily journaling on people with asthma. Some people think that journaling allows for the release of pent-up emotions and helps reduce stress overall.

Other Considerations:

Warnings and Precautions

Long-term treatment with theophylline for asthma may reduce blood levels of vitamin B6.

Prognosis and Complications

People with asthma can live normal, active lives. Because asthma is a chronic illness, it requires self-care and monitoring over the long term, as well as close contact with your doctor. Most people with asthma have occasional attacks separated by symptom-free periods. Paying attention to your mood, lowering the stress in your life, and having a good emotional support system will help you take good care of yourself.