Disulfiram (sold under the trade names Antabuse and Antabus) is a drug discovered in the 1920s that is used to support the treatment of chronic alcoholism by producing an acute sensitivity to ethanol (alcohol). Disulfiram works by inhibiting the enzyme acetaldehyde dehydrogenase, which means many of the effects of a "hangover" are felt immediately after alcohol is consumed.
In the body, alcohol is converted to acetaldehyde, which is then broken down by aldehyde dehydrogenase. If the dehydrogenase enzyme is inhibited, acetaldehyde builds up and causes unpleasant effects. Disulfiram should be used in conjunction with counseling and support.
Disulfiram is also being studied as a treatment for cocaine dependence, as it prevents the breakdown of dopamine (a neurotransmitter whose release is stimulated by cocaine); the excess dopamine results in increased anxiety, higher blood pressure, restlessness, and other unpleasant symptoms. Several studies have reported that it has antiprotozoal activity, as well. Disulfiram is the subject of research for treatment of cancer and HIV (to activate the reservoir of HIV-infected resting CD4 cells).