Tardive dyskinesia: clinical and neuroendocrine response to low dose bromocriptine.
Twelve patients with a long-standing history of moderate to severe symptoms of tardive dyskinesia, which had remained stable for several months, participated in a 6-week trial with bromocriptine. All patients were receiving a concomitant neuroleptic medication and were treated with a low dose of bromocriptine (0.75 to 7.5 mg). Patients showed a modest overall improvement of 16.6%, with a trend for greater improvement in male patients (23.6%). Baseline prolactin levels in the female patients showed a positive correlation with age and duration of tardive dyskinesia symptomatology. Plasma prolactin levels 4 hours following administration of bromocriptine were negatively correlated with the dose of bromocriptine. There appears to be a differential sensitivity for prolactin and growth hormone response to bromocriptine at these low doses in the presence of chronic neuroleptic treatment.