Monoamine oxidase inhibitors in anxiety disorders.

Monoamine oxidase inhibitors (MAOI's) have been shown to be significantly superior to placebo in the treatment of some anxiety disorders, particularly agoraphobia and mixed anxiety--depressive states. There is no convincing evidence that MAOI's are effective treatment in pure anxiety states, whether or not panic is present as a major symptom, although they are effective in so-called endogenous anxiety. Many past published studies of MAOI's have yielded poor results because the drugs have been prescribed for insufficient time (less than four weeks) or at too low dosage. There are no important therapeutic differences between the MAOI's apart from the faster speed of response with the nonhydrazine compound, tranylcypromine. Treatment often has to be long-term, and some degree of pharmacological dependence may develop. A few clinical studies have compared the efficacy of MAOI's and tricyclic antidepressants in anxious disorders. There is growing evidence that MAOI's are somewhat more effective than tricyclic antidepressants in the treatment of anxiety disorders and when phobic anxiety is an important component of a depressive disorder.