For hypertension, can an Angiotensin Receptor Blocker (ARB) be added to an Angiotensin-Converting Enzyme Inhibitor (ACEI)?

Dual ACE Inhibitor and ARB Therapy for Hypertension

The combination of an ACE inhibitor and ARB is not recommended for the treatment of hypertension due to increased risk of adverse effects without additional clinical benefit.

Evidence Against Dual ACE Inhibitor and ARB Therapy

The 2020 International Society of Hypertension guidelines do not include the combination of ACE inhibitors and ARBs as a recommended treatment strategy for hypertension 1. Instead, they outline a step-wise approach that involves using different classes of antihypertensive medications when blood pressure targets are not achieved.

Multiple guidelines specifically caution against this combination:

• The American College of Cardiology and American Heart Association recommend against the routine combined use of ACE inhibitors and ARBs due to increased risks of adverse effects without significant clinical benefit 2

• The KDOQI Clinical Practice Guidelines explicitly state that "the use of a combination of ACE-Is and ARBs as a dual blockade of the RAS cannot be recommended at present" due to increased adverse events, particularly impaired kidney function and hyperkalemia 1

• The European Society of Cardiology considers routine combined use of ACE inhibitor, ARB, and aldosterone antagonist as potentially harmful 2

Adverse Effects of Dual Therapy

When ACE inhibitors and ARBs are used together, there is a significant increase in:

• Hyperkalemia (elevated potassium levels)
• Acute kidney injury
• Hypotension
• No demonstrated improvement in mortality or cardiovascular outcomes

Preferred Approach for Hypertension Management

For patients with hypertension, the recommended approach includes:

1. Initial therapy: Start with either an ACE inhibitor or ARB (not both), particularly in patients with albuminuria 1

2. If BP target not achieved: Add a dihydropyridine calcium channel blocker (CCB) or thiazide/thiazide-like diuretic 1

3. If further BP lowering needed: Add the third agent from the above classes (ACE inhibitor/ARB + CCB + thiazide/thiazide-like diuretic) 1

4. For resistant hypertension: Consider adding a mineralocorticoid receptor antagonist (spironolactone) or other agents (amiloride, doxazosin, eplerenone, clonidine, or beta-blocker) 1

Special Populations

• Patients with diabetes and CKD: ACE inhibitors or ARBs are preferred first-line agents for blood pressure treatment, especially with albuminuria ≥300 mg/g Cr 1

• Heart failure patients: While dual RAS blockade has shown some benefits in heart failure studies, the increased risk of adverse events outweighs the benefits in hypertension management 2

• Black patients: Consider starting with a low-dose ARB + dihydropyridine CCB or a dihydropyridine CCB + thiazide-like diuretic 1

Monitoring Recommendations

When using ACE inhibitors or ARBs (individually, not in combination):

• Monitor serum creatinine and potassium within 2-4 weeks after starting or changing dose 1
• Continue therapy unless serum creatinine rises by more than 30% within 4 weeks 1
• Manage hyperkalemia when possible rather than immediately stopping the medication 1

Bottom Line

While both ACE inhibitors and ARBs effectively lower blood pressure and provide cardiovascular and renal protection, using them in combination increases the risk of adverse effects without providing additional clinical benefit. The evidence strongly supports using either an ACE inhibitor OR an ARB as part of a comprehensive antihypertensive regimen, but not both simultaneously.