What is a common side effect of calcium-channel blockers when used for hypertension?

• A. Bradycardia
• B. Peripheral edema
• C. Hypokalemia
• D. Dry mouth

Answer: (B)

Calcium-channel blockers are commonly used to manage hypertension by relaxing blood vessels and reducing vascular resistance. One recognized side effect of these medications is peripheral edema, which is the swelling of the extremities, particularly the ankles and feet. This occurs because calcium-channel blockers promote vasodilation of the peripheral blood vessels, which can lead to increased hydrostatic pressure in the capillaries and subsequently cause fluid to leak into the surrounding tissues.

The occurrence of peripheral edema is particularly notable with dihydropyridine calcium-channel blockers, such as amlodipine and nifedipine, which primarily affect vascular smooth muscle. In contrast, other options presented do not commonly arise as side effects of calcium-channel blockers; for instance, bradycardia is more associated with non-dihydropyridine agents like verapamil and diltiazem, while hypokalemia and dry mouth are less directly linked to the action of calcium-channel blockers in hypertension treatment.