Effect of melperone, chlorpromazine, haloperidol, and diazepam on experimental anxiety in normal subjects.

An attempt was made to evaluate tranquilizing effects of three neuroleptic drugs (10 and 50 mg melperone, 1 mg haloperidol, and 50 mg chlorpromazine) and diazepam (10 mg) on experimental anxiety in normal subjects. This was done by studying the effects of the drugs on the anticipatory autonomic (skin conductance) response evoked during aversive classical conditioning. Diazepam, 50 mg melperone, and chlorpromazine completely abolished the anticipatory response, decreased the number of conditioned and unconditioned responses, and decreased skin conductance level. Treatment with 10 mg melperone and haloperidol had no effect on the conditioned and unconditioned responses.