a drug that has an antidepressant effect. The name, now rarely used, was introduced in the late 1950s by U.S. psychiatrist Nathan S. Kline (1916–1983) to identify monoamine oxidase inhibitors derived from iproniazid, which had been developed for control of tuberculosis. Iproniazid was discontinued as a tuberculosis drug because of its powerful effects on the central nervous system.