Five schizophrenics and one alcoholic with tardive dyskinesia were given bromocriptine for two 8-week periods. The first trial was made during neuroleptic treatment and the second following a 3 weeks' wash-out of neuroleptics. When neuroleptics were given bromocriptine was essentially without effects, but after the neuroleptics had been discontinued the same bromocriptine treatment caused amelioration of dyskinesia in three and aggravation in two subjects. During the second bromocriptine trial all schizophrenic patients showed deterioration of psychotic symptoms followed by a reduction of symptoms when bromocriptine was discontinued.