The effects of alcohol on psychological functions in normal volunteers after 8 days' treatment with pipequaline (PK 8165), diazepam or placebo.

The effects of daily administration for 8 days of 50 mg pipequaline, 10 mg diazepam and placebo were assessed in a double-blind cross-over study with 12 healthy volunteers. This study also tested for an interaction between the drugs and alcohol on the eighth day. Subjective ratings, psychomotor and memory performance were evaluated. Diazepam produced the typical pattern of changes, namely impairments in psychomotor performance and reductions in the retention of newly memorised information. In contrast, the effects of pipequaline were relatively minor. In general, neither drug potentiated the effects of alcohol on performance, only isolated instances of non-additive interactions occurring. Subjective reports revealed that whereas both active drugs increased feelings of calmness, this result was accomplished by pipequaline with considerably less drowsiness, no euphoria and a general absence of the adverse side effects of diazepam.