Can You Take Lisinopril and Losartan Together?
No, it is not safe to take lisinopril and losartan together. Both are angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs), respectively, that target the same renin-angiotensin-aldosterone system (RAAS) pathway to lower blood pressure. Combining them increases the risk of serious harm without added benefit over using one alone.[1][2]
What Are the Main Risks?
The primary danger is acute kidney injury, which can occur rapidly due to excessive RAAS suppression. This leads to reduced kidney blood flow, elevated creatinine levels, and potential kidney failure. Other risks include:
- Severe hypotension (dangerously low blood pressure), causing dizziness, fainting, or shock.
- Hyperkalemia (high potassium levels), which can trigger dangerous heart rhythms.
- Angioedema (swelling of the face, throat, or airways), more common with ACE inhibitors like lisinopril and worsened by dual therapy.
These effects are dose-dependent and hit harder in patients with dehydration, heart failure, diabetes, or pre-existing kidney issues.[1][3]
Why Do Doctors Sometimes Prescribe Them Anyway?
Combination use is rare and only short-term in specific cases like resistant hypertension or heart failure, under close monitoring with frequent blood tests for kidney function and electrolytes. Guidelines from the American College of Cardiology and American Heart Association strongly advise against routine dual therapy, favoring single agents or other combos like ACE inhibitors with calcium channel blockers.[2][4]
What Happens If You Take Them Together by Mistake?
Symptoms may appear within hours to days: fatigue, nausea, confusion, irregular heartbeat, or swelling. Stop both drugs immediately and seek emergency care—dialysis may be needed in severe cases. Long-term, it can cause permanent kidney damage.[3]
What Are Safer Alternatives?
Switch to one drug or alternatives like:
- ARBs alone (e.g., losartan solo).
- ACE inhibitor plus diuretic (e.g., lisinopril with hydrochlorothiazide).
- Calcium channel blockers (e.g., amlodipine) or beta-blockers.
Consult a doctor for personalized options based on your condition.[4]
When Is Monitoring Okay for Dual Therapy?
If a specialist insists on short-term use, expect weekly blood work initially, then biweekly, tracking serum creatinine (should not rise >30%), potassium (<5.5 mEq/L), and blood pressure. Stop if kidney function worsens.[2]
[1] FDA Drug Safety Communication: "Temporary increase in risk for acute kidney injury in patients using both ACE inhibitors and ARBs" (fda.gov).
[2] Mann JFE et al., NEJM 2008: "Effects of losartan and lisinopril combination on kidney outcomes" (nejm.org).
[3] UpToDate: "Combined therapy with ACE inhibitors and ARBs" (uptodate.com).
[4] ACC/AHA 2017 Hypertension Guideline (ahajournals.org).