In a 69-year-old woman on lisinopril 10 mg daily with a dry cough, what medication should be switched to?

Switch to an Angiotensin Receptor Blocker (ARB)

In this 69-year-old woman with dry cough on lisinopril 10 mg, you should discontinue the lisinopril immediately and switch to an angiotensin receptor blocker (ARB) such as losartan or valsartan. 1, 2

Why Discontinue Lisinopril

• ACE inhibitor-induced cough is a well-documented class effect occurring in 5-35% of patients, making it the most common pharmaceutical cause of chronic dry cough 1, 2
• The cough is not dose-related, so reducing the dose from 10 mg to a lower amount will not help 2, 3
• Switching to another ACE inhibitor (such as enalapril or ramipril) is futile because all ACE inhibitors cause cough through the same bradykinin-mediated mechanism 2, 4
• The American College of Chest Physicians gives a Grade B recommendation that discontinuation is the only uniformly effective treatment 1, 2

Risk Factors Present in This Patient

• Female gender is associated with higher incidence of ACE inhibitor-induced cough compared to males 2
• This patient's demographic profile increases her likelihood of experiencing this side effect 2

Recommended Replacement: ARBs

• ARBs (losartan, valsartan, or telmisartan) have a cough incidence comparable to placebo (15-20%) versus 60-69% with ACE inhibitors in patients with prior ACE inhibitor-induced cough 5, 6, 7
• The American College of Cardiology/American Heart Association provides a Class 1, Level A recommendation (highest level) for using ARBs in patients intolerant to ACE inhibitors due to cough 2
• Clinical trials demonstrate that valsartan 80 mg produces cough in only 19.5% versus 68.9% with lisinopril, with no significant difference from hydrochlorothiazide placebo 6

Expected Timeline for Cough Resolution

• After stopping lisinopril, the cough typically resolves within 1-4 weeks, with a median of approximately 26 days (3.5 weeks) 1, 2
• A minority of patients may require up to 3 months for complete resolution 1, 2
• If cough persists beyond 4 weeks after discontinuation, evaluate for alternative causes including gastroesophageal reflux disease, heart failure-related pulmonary congestion, or asthma 2

Specific ARB Dosing Recommendations

• Valsartan: Start at 40-80 mg once daily, can titrate up to 160 mg twice daily for optimal effect 2
• Losartan: Start at 50 mg once daily, demonstrated in trials to have similar cough incidence to hydrochlorothiazide (17-29%) versus lisinopril (62-69%) 5
• Allow at least 36 hours between the last lisinopril dose and starting the ARB to minimize adverse effects 2

Monitoring After the Switch

• Check blood pressure, renal function, and potassium levels within 1-2 weeks after initiating the ARB and after any dose changes 2
• Monitor for cough resolution over the subsequent 1-4 weeks 1, 2

Critical Pitfalls to Avoid

• Do not try alternative ACE inhibitors – the cough will recur with any agent in this class 2, 3, 4
• Do not reduce the lisinopril dose – ACE inhibitor-induced cough is not dose-dependent and persists at any dosage 2, 3
• Do not assume timing excludes ACE inhibitors – cough can develop within hours or be delayed for months to over a year after starting therapy 1, 2
• Do not overlook that ACE inhibitors sensitize the cough reflex, potentially amplifying cough from other causes 1, 2