Inhibition of elimination of caffeine by disulfiram in normal subjects and recovering alcoholics.

The kinetics of caffeine elimination were investigated in 10 normal male subjects and in 11 recovering alcoholics before and during disulfiram dosing. In normal subjects the total body clearance of caffeine declined 30% (142 to 99 ml/min) at the maintenance dose of disulfiram, 250 mg/day, and 29% (161 to 114 ml/min) at the loading dose of 500 mg/day. In recovering alcoholics, the total body clearance decreased from 333 to 253 ml/min, a 24% change. The mean caffeine t1/2 increased 39% and 34% in normal subjects after 250 and 500 mg disulfiram, respectively, and 29% in recovering alcoholics. The inhibition of caffeine elimination was moderate in most subjects. However, the clearance of caffeine decreased by greater than or equal to 50% after disulfiram in three of the 11 recovering alcoholics. These patients may have an increased risk of cardiovascular and cerebral excitation associated with higher concentrations of caffeine, which could complicate withdrawal from alcohol.