Tiapride in the treatment of tardive dyskinesia: a clinical and biochemical study.

The effect of tiapride treatment was investigated in 10 patients with tardive dyskinesia. The effects of the drug on the symptoms of tardive dyskinesia, parkinsonian symptoms, and patients' mental conditions were evaluated using standardized rating scales before and weekly during the 28-day drug trial. Patients were reassessed 14 days after withdrawal of tiapride. The symptoms of tardive dyskinesia significantly improved during treatment and deteriorated after tiapride was withdrawn. Parkinsonian symptoms remained unchanged both during and after treatment. The patients' mental conditions significantly improved while they were taking tiapride, and did not appreciably deteriorate after treatment was discontinued. Plasma prolactin levels increased significantly during treatment, while plasma dopamine-beta-hydroxylase activity did not change.