The Prolactin Response to Flutroline Hydrochloride in Schizophrenic Patients

: Flutroline hydrochloride, a gamma carboline manifesting neuroleptic activity, was administered in a double-blind fashion in single daily dosages of 1, 5, 10, 20, and 100 mg to 48 hospitalized schizophrenic patients over a period of four weeks. During this period, weekly evaluations were made of response employing standardized psychiatric ratings. Plasma prolactin (PRL) levels were obtained at the termination of previous neuroleptic medication and at two-week intervals during treatment with the investigational compound. Examination of the initial PRL levels indicated that they could be grouped into those above, within, and below the normal range. Comparisons of these initial levels with those following the administration of flutroline suggested an improved methodology for determining optimal neuroleptic dosage.