Which side effect is associated with calcium channel blockers in some patients?

Study for the Medical Council of Canada Qualifying Examination (MCCQE) I. Engage with flashcards and multiple-choice questions with detailed feedback. Prepare confidently!

Calcium channel blockers can have hormonal effects beyond lowering blood pressure. In some patients, these drugs are associated with increased prolactin levels, which can result in galactorrhea. The proposed mechanism involves calcium signaling in the pituitary lactotrophs influencing prolactin secretion, and certain agents (notably verapamil and, less commonly, diltiazem) have been linked to this effect. While other side effects listed are not typical for calcium channel blockers—hyperkalemia relates more to inhibitors of the renin–angiotensin system, and hair loss or hyperglycemia are not characteristic respiratory of CCBs—the association with elevated prolactin and galactorrhea makes this option the best choice.