Warfarin Effect Enhanced by Disulfiram

To the Editor:—  Two drugs given together may antagonize or potentiate one another, have additive effects, increase combined therapeutic efficacy, or produce toxic conditions not associated with either alone. The chance of such occurrence is of course greater if their modes of action are related.Disulfiram (Antabuse) and warfarin (Coumadin) sodium both act upon, or within, the liver cell. Disulfiram competes with nicotinamide adenine dinucleotide for the active centers of the enzyme aldehyde dehydrogenase, and also decreases the oxygen consumption and the xanthine oxidase, succinoxidase, and catalase activity of liver homogenates.¹ Warfarin inhibits enzyme systems in the liver cell which synthesize prothrombin.¹ No reports were found, in a rapid survey of the literature, of patients who received both drugs at the same time.

Report of a Case: —  A 45-year-old man with chronic alcoholism for 20 years, apparently secondary to a psychoneurotic anxiety reaction, was treated unsuccessfully for