Gold salts have been adminitered to asthmatic patients based on the benefit of this drug in patients with rheumatoid arthritis. Small numbers of patients have been treated with gold injections or an oral gold compound called auranofin, and individual patients have been reported to reduce their symptoms and steroid requirements. Studies of large numbers of patients are lacking and this approach is not without adverse effects, since gold may also cause pulmonary fibrosis. For these reasons, the use of gold salts in the treatment of asthma must be regarded as investigational.
Troleandomycin (TAO) , an antibiotic, has been administered to asthmatic patients who have been steroid dependent. It appears to simply slow the excretion of one of the oral corticosteroids, methylprednisolone. Selected patients receiving methylprednisolone who are given troleandomycin have been able to reduce their steroid dosage. A similar effect of TAO has been noted on theophylline breakdown. For this reason, blood levels of theophylline are required of patients maintained on this medication during TAO administration. TAO has no anti-inflammatory effect of its own and may cause liver damage. It must be concluded that TAO has little place in the routine treatment of bronchial asthma.
Antihistamines have long been regarded as contraindicated in asthmatics. This prohibition has stemmed from the drying effect antihistamines have on lung secretions and the greater potential for “plugging”of the bronchial tubes in asthmatic attacks. This adverse effect has clearly been documented in many patients. On the other hand, studies of large dosages of antihistamines in asthmatic patients have occasionally demonstrated a beneficial effect. This is not surprising, since histamine is one of the irritating substances involved in provoking an asthmatic attack.
Azelastine is an antihistamine that has undergone trials in Japan and other countries in patients with bronchial asthma. Despite early positive results no significant benefit has been proven in large numbers of patients. One adverse effect is drowsiness. This drug is not available in the United States.
Another antihistamine, Ketotifen, has been available for use in Europe for bronchial asthma. Tb date, studies do not demonstrate a significant beneficial effect. This agent may also cause drowsiness. Until further studies of additional agents are made available there can be no basis for the routine use of antihistamines for treatment of bronchial asthma. Antihistamines may be carefully administered for nasal or sinus disease if the patient is closely monitored by a physician.