Dopamine agonists have been succesfully used in the treatment of various clinical disorders associated with hyperprolactinemia. However all of them are associated with some side effects which differ in incidence and severity. We have compared the efficacy and side effects of lisuride with bromocriptine in the treatment of hyperprolactinemia.Twenty women with hyperprolactinemia were randomized to receive either oral lisuride or bromocriptine. Ten patients received lisuride 0.2 mg b.i.d. and other ten received bromocriptine 2.5 mg b.i.d. All of the patients were evaluated with computerized tomography for the presence of pituitary adenoma. Fasting blood samples were obtained weekly for four weeks and patients were asked to note the side effects. Both lisuride and bromocriptine decreased baseline prolactin values significantly by the fourth week of the treatment. The incidence of side effects were similiar in both groups.As a result, lisuride is found to be as effective as bromocriptine in the treatment of hyperprolactinemia with comparable side effects.