Effect of sulpiride on serum prolactin levels in humans

The effect of acute and chronic administration of sulpiride sulphate on serum prolactin levels in humans was studied. Six normal women and four normal men received an i.m. injection of 100 mg sulpiride at 0800 h. A control group received saline solution 0.9%. Blood samples were taken before and 30, 60 and 120 minutes after the injection. Serum prolactin was determined by a double antibody radioimmunoassay technique. Sulpiride induced in all subjects a quick and marked increment of serum prolactin levels with peak values at 30 minutes. At 120 minutes the levels remained high. In another experiment six post menopausal women received 150 mg of sulpiride orally during 10 days. Five of them had marked increments of circulating levels of prolactin at the end of treatment. It is suggested that sulpiride could be used in the dynamic functional exploration of hypothalamic-pitutiary system.