Flumazenil in alcohol withdrawal: a double-blind placebo-controlled study.

The purpose of the present study was to study gamma-aminobutyric acid (GABA)-A receptor function in alcohol-dependent subjects during withdrawal, using the benzodiazepine antagonist flumazenil. In particular, we wanted to examine the hypotheses that an endogenous inverse agonist ligand at the GABA-A benzodiazepine receptor (GBzR) is active during withdrawal (in which case flumazenil should be anxiolytic), or whether chronic alcohol intake results in a shift in sensitivity of the receptor in the inverse agonist direction (in which case flumazenil should be anxiogenic). Results from 15 alcohol-dependent subjects in a double-blind placebo-controlled cross-over study showed that flumazenil was neither anxiolytic nor anxiogenic, although withdrawal scores were reduced during the course of the study. The fact that flumazenil was not anxiogenic, as it is in panic disorder, suggests that the GBzR is functioning differently in these two clinically similar conditions.