The benzodiazepines have been considered largely free of neuro-endocrine effect. However, in a double-blind, random assignment, placebo controlled study of six young women in the first half of their menstrual cycle oral temazepam (20 mg) was found to significantly lower plasma cortisol and raise plasma prolactin. The impact on cortisol was significant at 40 min and persisted for 3 h (P<0.01) after="" oral="" ingestion.="" prolactin="" was="" significantly="" raised="" at="" 1="" h="" after="" ingestion="" only="">P<0.05). no="" impact="" on="" fsh="" or="" lh="" was="" noted.="" these="" findings="" are="" compatible="" with="" recent="" reports="" of="">-aminobutyric acid and benzodiazepine binding sites in human pituitary tissue. The positive and negative aspects of these findings for the clinician are discussed.