A post-marketing surveillance study of Euhypnos (temazepam), a new short-acting benzodiazepine hypnotic. A total of 12,350 patients requiring a sleep inducer were treated for up to 3 months with doses of 10-30 mg at night. After 2 weeks 80% of First Reports (FRs) rated Euhypnos effective and at 3 months this had risen to 92% of 3062 Second Reports (SRs). Hangover was reported in 7% of FRs and 2% of SRs but in general the drug was well tolerated with adverse reactions consisting mainly of morning nausea, headache, drowsiness and vivid dreaming. Eighty-seven per cent of FRs and 93% of SRs were 'Clean' reporting no hangover, adverse reaction or event of any kind.