[Preclinical study of the safety of a new tranquilizer, phenazepam].

Chronic toxicity of the benzodiazepine series tranquilizer phenazepam (5 and 50 mg/kg) administered per os for 1.3 and 6 months was studied in experiments on white rats, guinea pigs and dogs. It has been shown during varying time of observation that the drug neither decreases weight gain in the animals nor adversly acts on the blood or produces local irritating action. Histopathological changes in some internal organs proved irreversible. Administered at varying periods of pregnancy, phenazepam at an oral dose of 100 mg/kg exerted no embryotoxic or teratogenic action.