Bromocriptine therapy in chronic schizophrenia: effects on symptomatology, sleep patterns, and prolactin response to stimulation.

Ten chronic schizophrenic patients were given bromocriptine in doses increasing from 1.25 to 5 mg over 6 days (the low-dose therapy) and then up to 40 mg over 15 days (the high-dose therapy). Psychopathological status was assessed using the Brief Psychiatric Rating Scale, twice daily the first 6 days, and every 2 days thereafter. The prolactin (PRL) response to haloperidol stimulation (1 mg i.v.) was measured in five cases before and 3 days after the end of high-dose therapy, and in one patient before and 3 days after the end of low-dose therapy. Electroencephalographic sleep studies were carried out before therapy and every 2 nights during low-dose therapy in five patients, and in two cases during high-dose therapy. Bromocriptine therapy modified neither clinical symptomatology nor sleep patterns. The PRL response to haloperidol after therapy was markedly lower than that before therapy in the five patients treated with high doses, and markedly higher in the single patient tested who was treated only with low-dose therapy.