Which drug class is most commonly associated with peripheral edema, as illustrated by the hypothetically edema-inducing drug lercandipine?

• A. ACE inhibitors
• B. Calcium channel blockers
• C. Beta blockers
• D. Diuretics

Answer: (B)

Peripheral edema from antihypertensives is most often caused by drugs that dilate arteries, increasing capillary hydrostatic pressure in the legs and pushing fluid into surrounding tissues. Calcium channel blockers of the dihydropyridine type are classic for this effect because they preferentially dilate precapillary arterioles. That stronger arteriolar dilation raises pressure in the distal capillaries, leading to fluid leakage and ankle/foot swelling. This edema is a common, dose-related adverse effect with these agents and can sometimes be mitigated by slower titration or added diuretic therapy, though the swelling may persist.

Other classes are less typically associated with this pattern. ACE inhibitors can cause edema via angioedema, but that’s a different mechanism and presentation. Beta blockers aren’t known for peripheral edema as a major adverse effect, and diuretics actually help reduce edema rather than cause it. Thus, the drug class most linked to this edema phenomenon is calcium channel blockers.