Sexual dysfunction is common in depressive illness, most often occuring as loss of sexual interest, impotence, and a decline in the frequency of intercourse. Antidepressant drugs have been documented to improve sexual function in depression; however, adverse effects of sexual function also occur as a result of the drugs' interference with peripheral cholinergic and adrenergic function. MAO inhibitors may also ameliorate depression-related sexual dysfunction. These drugs also improve sperm count and sperm motility and may have a clinical use in moderate oligospermia. Stimulant drugs have been linked to a wide variety of sexual effects. Most dramatic is the increase in sexual arousal reported by many stimulant users. Increases in sexual activity and sexual perversion have both been related to stimulant use. Due to the high rate of pre-drug sexual aberration and the non-specific nature of stimulant arousal, caution should be exercised in postulating a direct effect on sexuality by stimulant drugs.