Which anti-hypertensive drug class is specifically contraindicated in bilateral renal artery stenosis because it removes the angiotensin II-dependent efferent arteriolar tone that maintains GFR?
- A Calcium channel blockers
- B ACE inhibitors and angiotensin receptor blockers ✓
- C Thiazide diuretics
- D Alpha-1 blockers
Correct answer: B. ACE inhibitors and angiotensin receptor blockers
Explanation
In bilateral renal artery stenosis, perfusion pressure in the afferent arterioles is reduced. The kidneys compensate by angiotensin II-mediated efferent arteriolar constriction to maintain intraglomerular pressure and GFR. ACE inhibitors and ARBs abolish this efferent constriction, precipitating acute kidney injury. CCBs, thiazides, and α-blockers do not specifically act on this mechanism.
Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.