Long-term nitrazepam treatment in psychiatric out-patients with insomnia.

Psychiatric patients (N = 26) were treated chronically (from 1 week to 12 years) with nitrazepam, because of insomnia. The patients gave their subjective estimations of the effects and side effects of nitrazepam. The concentrations of nitrazepam in the plasma were measured by 63Ni-EC-gas-liquid chromatography. The pharmacokinetics of nitrazepam were compared between the psychiatric patients and healthy volunteers (N = 11). The steady-state concentrations and the half-life of nitrazepam in the psychiatric patients were comparable to those of the healthy volunteers. The subjective hypnotic effect of nitrazepam was mostly good or satisfactory and remained unchanged during long-term treatment. Only a few, mild side effects were reported. Nitrazepam does not seem to cause enzyme induction with lowered plasma levels and may therefore be of special value in the treatment of chronic insomnia.