A review of the literature showed that a high incidence or prevalence of depression in patients being treated with alpha-methyldopa has never been documented. In their study of hypertensive patients in a general medical clinic the authors found that symptoms of depression were no more common in 42 patients treated with alpha-methyldopa than in 38 patients treated with other antihypertensive agents. As with other centrally active agents, alpha-methyldopa appears able to produce many different behavioral symptoms, including mood changes, in predisposed individuals. Because alpha-methyldopa is a DOPA decarboxylase inhibitor but does not consistently affect mood or induce depression, its effects do not support a catecholamine hypothesis of depression.