Spironolactone and Lisinopril: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 2, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Spironolactone
Lisinopril
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
You've been prescribed two medicines that can each raise the level of potassium in your blood. Spironolactone is a "potassium-sparing" water pill, meaning it helps your body hold on to potassium. Lisinopril also nudges potassium upward. Used together, they can push your potassium higher than either one alone.
Too much potassium can affect your heart rhythm, so this matters. The good news is that this is very manageable. Your care team can keep you on both if they're right for you, and they'll usually check your potassium with a simple blood test. Please don't stop either medicine on your own, and let your doctor or pharmacist know if you feel unusually weak, tired, or have an irregular heartbeat.
Effect: Additive hyperkalemia. Lisinopril (ACE inhibitor) lowers aldosterone, reducing renal potassium excretion; spironolactone (aldosterone antagonist / potassium-sparing diuretic) compounds potassium retention. Neither is a prodrug relevant here; the effect is pharmacodynamic, not metabolic.
- Direction/magnitude: Serum K+ may rise ~1 to 1.5 mEq/L versus monotherapy.
- Onset: Delayed. Evidence: Probable. Severity: Major (rare arrhythmias, deaths reported).
- Management: Baseline and periodic serum potassium and renal function; increased vigilance with CKD, diabetes, elderly, volume depletion, or other K+-raising agents. Individualize dosing; counsel on hyperkalemia symptoms.
What happens
Increased risk of hyperkalemia
Interaction Deep Dive
By reducing aldosterone, angiotensin-converting enzyme (ACE) inhibitors can promote the retention of potassium1. When a potassium-sparing diuretic (spironolactone, canrenoate potassium, aMILoride, triamterene) is taken together with an ACE inhibitor, reports indicate that serum potassium rises by 1 to 1.5 mEq/L relative to what is seen with either agent alone23. In some instances, this elevation has led to serious arrhythmias and fatalities45.
Why it happens (mechanism)
Increased potassium retention secondary to lowered aldosterone levels
How to manage this interaction
This combination is used intentionally in some patients (for example in heart failure), so the key is careful monitoring rather than avoidance.
- Keep taking both exactly as prescribed unless your prescriber tells you otherwise.
- Expect your team to check your potassium and kidney function with blood tests, both at the start and periodically.
- Your doses may need to be adjusted and individualized by your care team based on those results.
- Avoid extra potassium (salt substitutes, potassium supplements) unless your doctor approves.
- Report muscle weakness, tingling, palpitations, or an irregular heartbeat promptly.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
2 reports — tap to read
a) A study assessed the safety of combining an ACE inhibitor (captopril) with a thiazide/potassium-sparing diuretic in 332 hypertensive patients whose blood pressure had not been brought to normal by the diuretics alone. Only a single instance of hyperkalemia (6 mmol/liter) was observed, along with a very low rate of hypotension (1.6%) 6.
b) The consequences of adding spironolactone to an ACE inhibitor and a loop diuretic were investigated in 214 patients with severe chronic congestive heart failure. Participants were randomly assigned to one of five parallel treatment arms: placebo or spironolactone given once daily at 12.5 mg, 25 mg, 50 mg, or 75 mg over 12 weeks. Hypokalemia (serum potassium below 3.4 mmol/L) was seen in 10% of those receiving placebo and in 0.5% of the spironolactone group. The rate of hyperkalemia (serum potassium at or above 5.5 mmol/L) was 5% in the placebo group, while it was 5%, 13%, 20%, and 24% in the 12.5-, 25-, 50-, and 75-mg spironolactone treatment arms, respectively. Factors that predicted hyperkalemia included the use of ACE inhibitors other than captopril, ACE inhibitor dose, and elevated baseline serum creatinine or potassium levels. The authors determined that daily doses of 12.5 mg to 25 mg of spironolactone given together with conventional therapy consisting of ACE inhibitors, loop diuretics, and digitalis are relatively safe, as long as serum potassium levels are monitored 7.
Common questions
Can I take Spironolactone and Lisinopril together?
Taking spironolactone and lisinopril together can raise your blood potassium, which can affect your heart rhythm, so your care team will monitor your potassium with blood tests and adjust doses as needed. Keep taking both as prescribed and report weakness or an irregular heartbeat. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Spironolactone and Lisinopril interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "delayed". Effects tend to build up gradually over days to weeks.
How is the Spironolactone and Lisinopril interaction managed?
This combination is used intentionally in some patients (for example in heart failure), so the key is careful monitoring rather than avoidance. Keep taking both exactly as prescribed unless your prescriber tells you otherwise. Expect your team to check your potassium and kidney function with blood tests, both at the start and periodically. Your doses may need to be adjusted and individualized by y… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Spironolactone or Lisinopril need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (7)
- Product Information: Prinivil(R), lisinopril. Merck & Co. Inc. Whitehouse Station, NJ, 2003. DailyMed
- Armayor GM & Lopez LM: Lisinopril: a new angiotensin-converting enzyme inhibitor. Drug Intell Clin Pharm 1988; 22:365-372. PubMed
- Burnakis TG & Mioduch HJ: Combined therapy with captopril and potassium supplementation. A potential for hyperkalemia. Arch Intern Med 1984; 144:2371-2372. DOI
- Lakhani M: Complete heart block induced by hyperkalemia associated with treatment with a combination of captopril and spironolactone (letter). Br Med J 1986; 293:271.
- Johnston RT, de Bono DP, & Nyman CR: Preventable sudden death in patients receiving angiotensin converting enzyme inhibitors and loop/potassium sparing diuretic combinations. Int J Cardiol 1992; 34:213-215. PubMed
- Schohn DC, Spiesser R, Wehrlen M, et al: Aldactazine/captopril combination, safe and effective in mild to moderate systemic hypertension: report on a multicenter study of 967 patients. Am J Cardiol 1990; 65:4K-6K. PubMed
- Anon: Effectiveness of spironolactone added to an angiotensin-converting enzyme inhibitor and a loop diuretic for severe chronic congestive heart failure (The Randomized Aldactone Evaluation Study (RALES)). Am J Cardiol 1996; 78:902-907.
Keep reading about Spironolactone
Keep reading about Lisinopril
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