Biochem/physiol Actions Cabergoline, a lysergic acid amide derivative, is a potent dopamine D2 receptor agonist. It also acts on dopamine receptors in lactophilic hypothalamus cells to suppress prolactin production in the pituitary gland. It has been used for monotherapy of Parkinson′s disease in the early phase; combination therapy, together with levodopa and a decarboxylase inhibitor such as carbidopa, in progressive-phase Parkinson′s disease and adjunctive therapy of prolactin-producing pituitary gland tumors (microprolactinomas).