A controlled comparative trial of mianserin and diazepam in the treatment of anxiety states in psychiatric out-patients.

Forty psychiatric out-patients with primary anxiety entered a double-blind trial comparing 2 weeks of treatment with mianserin 30--60 mg daily or diazepam 15--30 mg daily, followed by 2 weeks of single-blind placebo administration. Both drugs were effective anti-anxiety agents, but mianserin was significantly superior in efficacy as measured by the Physician's Global Rating of Severity of Illness. No differences between treatments were apparent using the Hamilton Rating Scale for Anxiety. There was no significant differences in terms of side-effects and both drugs increased anticholinergic effects such as dry mouth, blurred vision and constipation over baseline values. With one exception in the mianserin group, all patients who entered placebo treatment became worse.