What class of medication is first-line for hyperprolactinemia?

• A. Dopamine agonists
• B. Beta blockers
• C. SERMs
• D. ACE inhibitors

Answer: (A)

Dopamine agonists are used first because prolactin production by pituitary lactotrophs is inhibited by dopamine. Activating the D2 receptors on these cells suppresses prolactin secretion and often reduces tumor size in prolactin-secreting adenomas. This direct action lowers prolactin levels, helps restore normal menstrual cycles and fertility, and improves galactorrhea. Cabergoline is typically preferred due to strong efficacy and good tolerability; bromocriptine is a common alternative. Side effects can include nausea and dizziness, and ergot-derived agents carry rare risks like valvular heart disease. The other drug classes listed do not target prolactin production or secretion, which is why they are not first-line choices for hyperprolactinemia.