In 36 female patients with microprolactinoma was carried out a primary therapy and in 19 patients (10 males, 9 females) with a postoperatively persisting hyperprolactinaemia a secondary therapy with bromocriptine. In close correlation between the PRL-levels and the bromocriptine dose we achieved a normalisation of the hormone levels in the microprolactinomas. A normalisation of the cycle was observed in 80%, a persisting of the galactorrhoea in about 90% and a conception in nearly two thirds of the women. Also in those patients who underwent a secondary therapy in nearly 80% a decrease of the PRL-levels into the normal region developed. In a longterm therapy with bromocriptine a reduction of the dose may become possible, so that controls of the hormone levels are necessary in larger intervals. Most side effects of a bromocriptine treatment are transitory.