The efficacy of oxprenolol (Trasicor) and propranolol in controlling anxiety was compared in a double-blind study of patients with anxiety and tension. Efficacy was assessed by the investigator with the aid of a psychiatric rating scale consisting of 19 items, bythe patients using visual analogue scales, and by the investigator's and the patients' over-all assessments. Tolerance to the drugs was evaluated by over-all assessment and by means of a checklist of signs and symptoms which emerged during treatment. Little difference in the efficacy of the two drugs was observed. Both were effective in the treatment of anxiety and tension. In general, oxprenolol was significantly better tolerated than propranolol. Evidence of the intrinsic sympathomimetic activity of oxprenolol emerged during the course of the study or, alternatively, evidence that propranolol had a greater cardiac-depressant effect.