Should You Switch to an ARB for ACE Inhibitor-Induced Cough in Heart Failure?
Yes, switch to an angiotensin receptor blocker (ARB) immediately—but only after confirming the cough is truly ACE inhibitor-induced and troublesome enough to interfere with sleep or daily function. 1
Step 1: Confirm the Cough is ACE Inhibitor-Induced
Before switching medications, you must rule out other causes and establish causality:
Exclude pulmonary edema first, as cough is a cardinal symptom of worsening heart failure that requires intensification of diuretic therapy, not discontinuation of the ACE inhibitor 1
Recognize that cough is extremely common in heart failure patients due to smoking-related lung disease, making attribution challenging 1
ACE inhibitor-induced cough does not always require discontinuation—only when it becomes troublesome (e.g., preventing sleep) should you consider switching 1
The diagnosis is confirmed by withdrawal and rechallenge: cough should resolve within 1-4 weeks after stopping the ACE inhibitor, though it may take up to 3 months in some patients 1, 2
Step 2: Make the Switch to an ARB
Once you've confirmed ACE inhibitor-induced cough that warrants treatment change:
ARBs are the Class I, Level A recommendation for patients intolerant to ACE inhibitors due to cough, providing equivalent cardiovascular benefits without inhibiting bradykinin accumulation—the mechanism responsible for ACE inhibitor-induced cough 1, 3, 2
Specific ARB Options and Dosing:
Losartan: Start 25-50 mg once daily, titrate to target dose of 100 mg once daily 3
- In controlled trials, losartan produced cough in only 17-29% of patients with prior ACE inhibitor-induced cough, compared to 62-69% with lisinopril rechallenge 4
Valsartan: Start 40 mg twice daily (or 80 mg once daily), titrate to target dose of 160 mg twice daily 3, 5
- Cough incidence was 19.5% with valsartan versus 68.9% with lisinopril in head-to-head trials 5
Candesartan: Start 4-8 mg once daily, titrate to target dose of 32 mg once daily 3
Step 3: Implementation and Monitoring
Discontinue the ACE inhibitor immediately when making the switch—there is no need for overlap or washout period 1
Critical Safety Monitoring:
Check baseline renal function and potassium before starting the ARB, then recheck within 1-2 weeks after initiation 1, 2
Acceptable biochemical changes include:
Monitor blood chemistry every 4 months thereafter once stable 1
Dose Titration Strategy:
Double the ARB dose at 2-4 week intervals if blood pressure remains elevated and the medication is well-tolerated 1, 2
Aim for evidence-based target doses shown to reduce cardiovascular events in clinical trials, but accept intermediate doses if targets are not tolerated—some ARB is better than none 1, 2
Critical Pitfall: Angioedema Risk
Although rare (<1%), angioedema can occur with ARBs in patients who previously experienced angioedema with ACE inhibitors—use caution during initial treatment and counsel patients to report lip, tongue, or throat swelling immediately 1, 3, 2
If angioedema occurs with an ARB, discontinue immediately and avoid all ARBs for the patient's lifetime 2
What About Continuing the ACE Inhibitor?
Approximately 30% of patients with confirmed ACE inhibitor-induced cough will not develop cough after a third trial of ACE inhibitor therapy, and some patients experience spontaneous resolution of cough despite continuing treatment 3, 6
However, in the context of heart failure with multiple guideline-directed medical therapies already on board (beta-blocker, MRA, SGLT2 inhibitor, loop diuretic), the pragmatic approach is to switch directly to an ARB rather than attempt rechallenge, as this minimizes treatment interruption and maintains renin-angiotensin system blockade 1, 7
Expected Timeline for Cough Resolution
Cough typically resolves within 1-4 weeks after discontinuing the ACE inhibitor, though it may persist up to 3 months in some patients 1, 3, 2
If cough persists beyond 3 months after switching to an ARB, investigate alternative causes of chronic cough 1