Clinical evaluation of diphenhydramine hydrochloride for the treatment of insomnia in psychiatric patients: a double-blind study.

Kudo Y, Kurihara M.

Institute of Clinical Pharmacology, Aino Hospital, Osaka, Japan.

The usefulness of the antihistaminic agent diphenhydramine hydrochloride was evaluated using a double-blind procedure at sleeping doses of 12.5, 25, and 50 mg in 144 psychiatric patients with insomnia.

The general condition of the patients with insomnia was at least "slightly improved" in 62.5% (12.5-mg group), 60% (25-mg group), and 67.4% (50-mg group) after treatment with the test drug for 2 weeks. Side effects were observed in a total of 11 patients (7.6%) but were not severe.

No symptoms suggestive of drug dependence were evident.

Diphenhydramine hydrochloride thus appears to be effective in the treatment of insomnia, but the appropriate dosage will depend on previous medical treatment of insomnia.

[link to www.ncbi.nlm.nih.gov]