Asthma Health Article

Drugs

The chief methylxanthine drug is theophylline. It may exert some anti-inflammatory effect and is especially helpful in controlling nighttime symptoms of asthma. When, for some reason, a patient cannot use an inhaler to maintain long-term control, sustained-release theophylline is a good alternative. The blood levels of the drug must be measured periodically, as too high a dose can cause an abnormal heart rhythm or convulsions.

Beta-receptor agonists (drugs that trigger cell response) are bronchodilators. They are the drugs of choice for relieving sudden attacks of asthma and for preventing attacks from being triggered by exercise. Some agonists, such as albuterol, act mainly in lung cells and have little effect on the heart and other organs. These drugs generally start acting within minutes, but their effects last only four to six hours. They may be taken by mouth, inhaled, or injected. In 2004, a new lower concentration of albuterol was approved by the FDA for children ages two to 12.

Steroids are drugs that resemble natural body hormones. They block inflammation and are effective in relieving symptoms of asthma. When steroids are taken by inhalation for a long period, asthma attacks become less frequent as the airways become less sensitive to allergens. Steroids are the strongest medicine for asthma, and can control even severe cases over the long term and maintain good lung function. However, steroids can cause numerous side effects, including bleeding from the stomach, loss of calcium from bones, cataracts in the eye, and a diabetes-like state. Patients using steroids for lengthy periods may also have problems with wound healing, may gain weight, and may suffer mental problems. In children, growth may be slowed. Besides being inhaled, steroids may be taken by mouth or injected, to rapidly control severe asthma.

Leukotriene modifiers are among a newer type of drug that can be used in place of steroids, for older children or adults who have a mild degree of persistent asthma. They work by counteracting leukotrienes, which are substances released by white blood cells in the lung that cause the air passages to constrict and promote mucus secretion. Other drugs include cromolyn and nedocromil, which are anti-inflammatory drugs that often are used as initial treatments to prevent long-term asthmatic attacks in children. Montelukast sodium (Singulair) is a drug taken daily that is used to help prevent asthma attacks rather than to treat an acute attack. In 2004, the FDA approved an oral granule formula of Singulair for young children.

If a patient's asthma is caused by an allergen that cannot be avoided and it has been difficult to control symptoms by drugs, immunotherapy may be worth trying. In a typical course of immunotherapy, increasing amounts of the allergen are injected over a period of three to five years, so that the body can build up an effective immune response. There is a risk that this treatment may itself cause the airways to become narrowed and bring on an asthmatic attack. Not all experts are enthusiastic about immunotherapy, although some studies have shown that it reduces asthmatic symptoms caused by exposure to dust mites, ragweed pollen, and cats.

Managing asthmatic attacks

A severe asthma attack should be treated as quickly as possible. It is most important for a patient suffering an acute attack to be given extra oxygen. Rarely, it may be necessary to use a mechanical ventilator to help the patient breathe. A beta-receptor agonist is inhaled repeatedly or continuously. If the patient does not respond promptly and completely, a steroid is given. A course of steroid therapy, given after the attack is over, will make a recurrence less likely.

Long-term allopathic treatment for asthma is based on inhaling a beta-receptor agonist using a special inhaler that meters the dose. Patients must be instructed in proper use of an inhaler to be sure that it will deliver the right amount of drug. Once asthma has been controlled for several weeks or months, it is worth trying to cut down on drug treatment, but this tapering must be done gradually. The last drug added should be the first to be reduced. Patients should be seen every one to six months, depending on the frequency of attacks. Starting treatment at home, rather than in a hospital, makes for minimal delay and helps the patient to gain a sense of control over the disease. All patients should be taught how to monitor their symptoms so that they will know when an attack is starting. Those with moderate or severe asthma should know how to use a flow meter. They also should have a written plan to follow if symptoms suddenly become worse, including how to adjust their medication and when to seek medical help. If more intense treatment is necessary, it should be continued for several days. When deciding whether a patient should be hospitalized, the physician must take into account the patient's past history of acute attacks, severity of symptoms, current medication, and the availability of good support at home.