Cabergoline (CBG)

Cabergoline is a potent dopamine receptor agonist on D2 receptors. Rat studies show cabergoline has a direct inhibitory effect on pituitary lactotroph (prolactin) cells. It is frequently used as a first-line agent in the management of prolactinomas due to higher affinity for D2 receptor sites, less severe side effects, and more convenient dosing schedule than the older bromocriptine. Cabergoline is a long-acting dopamine D2 receptor agonist and in vitro rat studies show a direct inhibitory effect on the prolactin secretion in the pituitary's lactotroph cells. Cabergoline decreased serum prolactin levels in reserpinized rats. Receptor binding studies indicate a low affinity for dopamine D1 receptors, α1-adrenergic receptors, and α2-adrenergic receptors. Relatively little is known about the effects of this medication during pregnancy and lactation. In some cases the related bromocriptine may be an alternative when pregnancy is expected.