Flunitrazepam versus placebo premedication for minor surgery.

The clinical effects of oral flunitrazepam (2 mg on the night before operation followed by 2 mg on the morning of operation) and placebo as premedicants were tested in a double-blind study in 81 gynaecological patients. The separate or total concentrations of flunitrazepam and its demethylated metabolite in plasma (measured by gas chromatography) were correlated with the clinical effects of flunitrapam premedication, assessed both sugjectively and objectively. In most parameters tested (sleep on the night before operation, sedation, apprehension, headache, pulse rate), there was a positive, significant difference between the flunitrazepam group (n = 44) and the placebo group (n = 37). No significant difference was found between the two groups in emetic effect, excitement, systolic blood pressure increase, and vene-puncture, but the patients receiving flunitrazepam felt significantly more dizziness. The temperature of the left forefinger before, during and after the anaesthesia did not vary significantly between the two groups. There was no correlation between the plasma concentration of flunitrazepam and its demethylated metabolite (separate or total concentrations) and any of the parameters tested before induction of anaesthesia. Flunitrazepam is a new oral premedicant with prominent sedative and anxiolytic actions. When the drug is given as a sedative on the night before operation, followed by a second dose on the morning of operation, the beneficial effects last for at least 8 hours after the second dose.