More than 50 million people in the U.S. suffer from asthma and allergies. Fortunately, today there are many effective medications available to treat these conditions. The following information is intended to help asthma and allergy sufferers better understand the most commonly used types of medications.

  • Antihistamines

If you have allergies, your physician may prescribe antihistamines, which are used to relieve or prevent the symptoms of allergic rhinitis (hay fever) and other allergies. Antihistamines can lessen your symptoms by preventing the effects of histamine—a chemical substance produced by the body during an allergic reaction. Antihistamines, which come in tablet, capsule, liquid or injection form, are available by prescription as well as over-the-counter.

Most over-the-counter antihistamines can cause drowsiness. Newer prescription antihistamines rarely cause this side effect. Other common side effects of antihistamines include dehydration—dry mouth, difficulty urinating, dry eyes or constipation. After taking antihistamines, some children may experience nightmares, unusual jumpiness or nervousness, restlessness or irritability.

  • Decongestants

Decongestants are used to treat nasal congestion and other symptoms associated with colds and allergies. They work by shrinking blood vessels, thereby decreasing the amount of fluid that leaks out and lessening nasal congestion. Decongestants are available in liquid and tablet form, both over-the-counter and by prescription. Many medications combine both antihistamines and decongestants to relieve a larger range of symptoms. Side effects of decongestants can include nervousness, sleeplessness or elevation in blood pressure.

Decongestants are also available in nose spray or drop form for acute congestion. However, over-the-counter nasal sprays should not be used more than three to four days in a row. If used for a prolonged period of time, over-the-counter nose sprays can cause “rebound rhinitis,” actually increasing your nasal congestion. Prescription nasal sprays and drops do not have this effect and can be used for longer periods of time, as prescribed by your physician.

  • Anti-inflammatory agents

People with asthma have inflamed airways. This inflammation causes the bronchi—the main branches leading from the throat to the lungs—to become overly reactive. The airways are more sensitive to various asthma triggers such as allergens, cold and dry air, smoke and viruses. Anti-inflammatory agents such as cromolyn , nedocromil and corticosteroids reduce inflammation and asthma symptoms. Cromolyn and nedocromil are non-steroidal and usually are prescribed in the inhaled form, while corticosteroids are prescribed in both the inhaled (topical) and oral form.

Corticosteroids are sometimes also referred to as steroids.” This type of medication is not related to the anabolic steroids that are misused by some athletes to increase performance. Rather, corticosteroids have been used as a successful treatment for asthma and allergies since 1948. They decrease airway inflammation and swelling in the bronchial tubes; reduce mucus production by the cells lining the bronchial tubes; decrease the chain of overreaction (hyperreactivity) in the airways; and help the airway “smooth muscle” respond to other medications.

Corticosteroids can be administered in a variety of ways. Topical preparations (on specific surface areas such as skin or the lining of the bronchial tubes) may be applied as creams or sprays (inhalers). Corticosteroid inhalers are recommended for patients with daily, moderate or severe asthma symptoms. Oral corticosteroids may be ingested in a liquid or tablet form, or may be administered by injection. They are generally only prescribed for those with severe asthma symptoms.

Some people may experience minor side effects of hoarseness and thrush (a fungal infection of the mouth and throat) from using corticosteroid inhalers. Such problems can be minimized by mouth-rinsing and using a spacer device, which can reduce the amount of medication residue in the mouth and throat. Although there are conflicting studies, long-term use of inhaled corticosteroids may result in reduced growth velocity in children. However, control of asthma symptoms may be of greater importance. If you are concerned about your child using these medications on a long-term basis, see your physician for more information.

Oral corticosteroids can have more side effects than inhaled corticosteroids. Long-term use of oral corticosteroids is not recommended, except in cases of uncontrolled, severe asthma. Your doctor will prescribe oral steroids for long durations only when other treatments have failed to restore normal lung function and the risks of uncontrolled asthma are greater than the side effects of the steroids. Prednisone, one of the most commonly prescribed steroid drugs, is available in tablet or liquid form. Possible side effects of short-term prednisone use include slight weight gain, increased appetite, menstrual irregularities and cramps, heartburn, or indigestion. Some patients experience side effects such as loss of energy, poor appetite, and severe muscle aches or joint pains when their dosage of cortisone tablets is decreased. If you are taking oral steroids, your physician will taper your dosage slowly for weeks or months to avoid effects of withdrawal.

Long-term oral corticosteroid use may cause side effects such as ulcers, weight gain, cataracts, weakened bones and skin, high blood pressure, elevated blood sugar, easy bruising and decreased growth in children. If you have questions or concerns about long-term oral steroid use, make sure to discuss them with your physician.

Corticosteroids, when taken properly, are a very effective method of treatment for asthma and allergies. To achieve their desired effects, you should always take them in the dosage prescribed. Do not increase or decrease your medication without first consulting your physician. Also, it is important to follow the prescribed frequency and use the proper inhaler technique to administer the medication. Please see the Tip brochure in this series for more information on the use of inhaled medications for asthma.

  • Anti-leukotrienes

Many of the cells involved in causing airway inflammation are known to produce potent chemicals within the body called leukotrienes (lu-ko-try-eens). Leukotrienes are responsible for inciting a riot within the body—causing the contraction of the airway smooth muscle, increasing leakage of fluid from blood vessels in the lung, and further promoting inflammation by attracting other inflammatory cells into the airways.

Recently, oral anti-leukotriene medications have been introduced to fight the inflammatory response typical of allergic disease. These drugs are used in the treatment of chronic asthma. Recent data demonstrates that prescribed anti-leukotriene medications can be beneficial for many patients with asthma. Additionally, many patients may find it easier and prefer taking an oral rather than an inhaled medication. These newer medications will eventually have an increased role in asthma care as more studies are conducted.

  • Bronchodilators

Bronchodilators are generally used as asthma “rescue medications” to relieve coughing, wheezing, shortness of breath and difficulty in breathing. They work by opening up the bronchial tubes—the air passages in the lungs—so that more air can flow through. Bronchodilators include beta-agonists, theophylline and anticholinergics. They come in inhaled, tablet, capsule, liquid or injectable forms.

Salmeterol is a long-acting bronchodilator that, along with an anti-inflammatory medication, is used for maintenance in the control of asthma symptoms. Other bronchodilators are intended to be used as rescue medications only during asthma flare-ups or when regular maintenance therapies are not working. Side effects of bronchodilators can include nervousness, restlessness and insomnia, and rarely, headache. Elderly patients and children may be more sensitive to the effects of these medications.