III. The Effect of Isoniazid and of Iproniazid in Patients with Rheumatoid Arthritis
DEPRESSION, exhaustion, anxiety, conversion, and other emotional reactions characteristically accompany chronic debilitating diseases and may limit the patients’ recovery from their primary disease or even prevent satisfactory improvement. To many of these patients the desirable effects that result from the administration of the hydrazides, especially iproniazid, include a generalized sense of well-being, increase in appetite, gain in weight, and decrease in fatigability. However, constipation, lightheadedness, postural hypotension, dysuria, loss of libido, muscular irritability, hyperactivity of deep reflexes, paresthesia, nervousness, excessive dreaming, and insomnia may also occur.28 At times, an increase in the frequency and the severity of convulsions occurs in epileptics, and psychotic episodes develop in predisposed patients.29 Discontinuation of the hydrazides after prolonged administration is at times associated with irritability, restlessness, excessive dreaming, headache, vertigo, and nausea. This “withdrawal syndrome” is observed more frequently after discontinuation of iproniazid than after isoniazid therapy. It usually appears within 24 to 48 hours after cessation of therapy and persists with gradual regression for approximately 10 to 14 days. Occasionally, vitamin-B deficiency syndromes occur, suggesting that under certain conditions these drugs may compete in the body with nicotinic acid.30 Today, most authorities believe that isoniazid is a safe drug for long-term usage but that iproniazid, in the dosage of 300 mg. daily used for the treatment of tuberculosis, too frequently produces toxic reactions. The mechanism of the action responsible for the effects of the hydrazides is not known, but it probably is related to an alteration in enzyme systems that affect certain components . . .