Cabergolin

Cabergoline is an ergot-derived dopamine receptor agonist used primarily to treat hyperprolactinemia and prolactin-secreting pituitary adenomas. It acts as a potent agonist at dopamine D2 receptors on pituitary lactotroph cells, inhibiting prolactin secretion and often causing shrinkage of prolactinomas. By lowering prolactin levels, cabergoline can restore ovulatory function and reduce galactorrhea and other symptoms of excess prolactin. It has also been used off-label as an adjunct in Parkinson’s disease and, less commonly, in other conditions associated with prolactin excess.

The medication is given orally, typically in divided doses. A common starting regimen is 0.25 mg taken twice weekly, with gradual increases based on response and tolerability. Maintenance dosing is usually in the range of 0.5 to 2 mg per week, though doses are individualized and higher doses may be used in selected cases under careful supervision. Cabergoline has a long elimination half-life, allowing for infrequent dosing, but requires monitoring for adverse effects.

Common adverse effects include nausea, dizziness, headaches, fatigue, orthostatic hypotension, constipation, and nasal congestion. More serious but less common risks include valvular heart disease with long-term high-dose use and impulse control disorders. Because of potential cardiac effects, baseline and ongoing cardiac evaluation (such as echocardiography) is advised for long-term or high-dose therapy.

Contraindications include pregnancy and lactation unless specifically advised by a clinician. Caution is warranted in individuals with known valvular heart disease, heart failure, peptic ulcers, or significant hepatic impairment. Drug interactions can occur with other dopaminergic or serotonergic agents and with medications that affect blood pressure.