Effects of granisetron and haloperidol, alone and in combination, on psychometric performance and the EEG.

1. The effects of granisetron (160 micrograms kg-1 body weight) and haloperidol (3 mg) on psychometric performance and the EEG were investigated in a randomised, single-blind, crossover, placebo controlled study of 12 healthy male volunteers. 2. There was evidence that haloperidol impaired psychometric performance; however its effects on the EEG were not clear cut. In contrast there was very little evidence to suggest that granisetron had any impact on performance or the EEG. 3. The findings from this study suggest that granisetron does not impair daytime function and that it can be co-administered with haloperidol without producing unwanted synergistic effects.