Compared with ACE inhibitors, an angiotensin II receptor blocker (ARB) is less likely to cause which side effect?

Compared with ACE inhibitors, an angiotensin II receptor blocker (ARB) is less likely to cause which side effect?

• A. Cough
• B. Angioedema
• C. Hyperkalemia
• D. Renal failure in bilateral stenosis

Answer: (A)

The key idea here is why cough occurs with ACE inhibitors but not with ARBs. ACE inhibitors block the enzyme that, among other actions, breaks down bradykinin. When bradykinin builds up, it can trigger a dry, persistent cough in many patients. ARBs, on the other hand, block the angiotensin II receptor without affecting bradykinin metabolism, so they do not typically cause that bradykinin-related cough. Other adverse effects can overlap between the two classes—hyperkalemia, and potential renal function changes in bilateral renal artery stenosis—so those aren’t uniquely more likely with ARBs. Angioedema can occur with both, though it’s less common with ARBs than with ACE inhibitors. But the cough distinction is the most characteristic difference, making cough the best answer.

The key idea here is why cough occurs with ACE inhibitors but not with ARBs. ACE inhibitors block the enzyme that, among other actions, breaks down bradykinin. When bradykinin builds up, it can trigger a dry, persistent cough in many patients. ARBs, on the other hand, block the angiotensin II receptor without affecting bradykinin metabolism, so they do not typically cause that bradykinin-related cough.

Other adverse effects can overlap between the two classes—hyperkalemia, and potential renal function changes in bilateral renal artery stenosis—so those aren’t uniquely more likely with ARBs. Angioedema can occur with both, though it’s less common with ARBs than with ACE inhibitors. But the cough distinction is the most characteristic difference, making cough the best answer.