Which of the following is an adverse effect of dihydropyridine calcium channel blockers?

Dihydropyridine calcium channel blockers, such as amlodipine and nifedipine, primarily act on the vascular smooth muscle to induce vasodilation, which can lead to several side effects. One common and notable adverse effect of these medications is peripheral edema. This occurs because the vasodilation can lead to increased hydrostatic pressure in the capillaries of the lower extremities, causing fluid to leak into the interstitial space. As a result, patients commonly experience swelling in the ankles and feet.

Reflex bradycardia is more typically associated with non-dihydropyridine calcium channel blockers, which can impact heart rate by decreasing conduction through the sinoatrial node. Dry cough is a known side effect of ACE inhibitors, not calcium channel blockers. Fatigue can occur with many medications but is not a specific or common adverse effect of dihydropyridine calcium channel blockers compared to peripheral edema. Therefore, identifying peripheral edema as the adverse effect directly linked to dihydropyridine calcium channel blockers highlights the specific response of the body to these medications.