Lisinopril and Candesartan: 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
Candesartan
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.
Candesartan (Atacand) and lisinopril (Prinivil, Zestril) work on the same body system that controls your blood pressure and fluid balance. Candesartan is an ARB and lisinopril is an ACE inhibitor. Taking both at once puts a "double block" on that system.
That extra blocking can push things too far. It may drop your blood pressure too low (causing dizziness or fainting), let potassium build up in your blood, and put stress on your kidneys. Because of this, doctors usually try to avoid using both together. If you were prescribed both, don't stop either one on your own. Please check with your pharmacist or doctor so they can review it and keep an eye on your blood pressure, kidneys, and potassium.
Mechanism: Dual RAAS blockade. Candesartan (ARB) blocks the AT1 receptor while lisinopril (ACE inhibitor) reduces angiotensin II formation. Neither is a prodrug relevant here; the combined effect is additive suppression of the renin-angiotensin-aldosterone axis.
Direction/effect: Increased risk of hypotension, syncope, hyperkalemia, and renal impairment (including acute renal failure), especially in atherosclerotic disease, heart failure, or diabetes with end-organ damage.
- Severity: Major; evidence established.
- Management: Generally avoid combined use. If necessary, monitor BP, serum potassium, and renal function (SCr/eGFR) closely; doses individualized by the care team.
What happens
Increased risk of adverse events (ie, hypotension, syncope, hyperkalemia, changes in renal function, acute renal failure)
Interaction Deep Dive
Combining an ACE inhibitor with an angiotensin receptor blocker (ARB), thereby imposing dual blockade on the renin-angiotensin-aldosterone system, has been linked to a greater frequency of adverse effects. Among patients with confirmed atherosclerotic disease, heart failure, or diabetes accompanied by end organ damage, giving an ACE inhibitor together with an ARB produced a higher rate of hypotension, syncope, hyperkalemia, and alterations in renal function (acute renal failure included) relative to the use of either drug by itself 3. As a rule, this combination should be avoided; nevertheless, if joint administration cannot be avoided, monitor blood pressure, renal function, and electrolytes carefully 4. A meta-analysis involving patients with left ventricular dysfunction found that supplementing ARB therapy with an ACE inhibitor raised the overall risk of adverse events that prompted therapy discontinuation, compared with ACE inhibitor therapy used alone 1.
Why it happens (mechanism)
Dual blockade of the renin-angiotensin-aldosterone system
How to manage this interaction
What your care team usually does:
- Generally avoids using an ACE inhibitor and an ARB together, and may consider whether one drug alone or a different medication is a better fit for you.
- If both are truly needed, they closely monitor your blood pressure, kidney function, and potassium, and may adjust and individualize your doses.
What you should do:
- Keep taking both exactly as prescribed unless your prescriber tells you otherwise.
- Ask your pharmacist or doctor to confirm both are meant to be taken together.
- Report dizziness, fainting, muscle weakness, or reduced urination promptly.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) A systematic review with meta-analysis involving 18,160 patients who had heart failure or left ventricular dysfunction, drawn from 9 randomized trials, showed that adding an angiotensin receptor blocker (ARB) to ACE inhibitor treatment was linked to a greater risk of adverse events resulting in discontinuation of therapy when compared with ACE inhibitor treatment by itself. Every patient had NYHA functional class II to IV heart failure, an ejection fraction of 45% or below, or left ventricular dysfunction acutely following myocardial infarction. The agents included were losartan, candesartan, valsartan, irbesartan, and telmisartan. Follow-up lasted from 4 weeks to 41 months. The analysis showed that combination therapy raised the risk of any adverse effect by 2.3%. The risk of hypotension rose 1.1%, the risk of worsening renal function rose 1%, and the risk of hyperkalemia rose 0.6%. Nevertheless, the risk of angioedema or cough was not significantly different between the treatment arms. When a combination approach is warranted, patients should be monitored closely for possible adverse effects 1.
Common questions
Can I take Lisinopril and Candesartan together?
Combining candesartan and lisinopril doubly blocks the same blood pressure system and raises the risk of low blood pressure, high potassium, and kidney problems, so this pairing is usually avoided. Don't change anything on your own; ask your pharmacist or doctor to review it. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Lisinopril and Candesartan interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How is the Lisinopril and Candesartan interaction managed?
What your care team usually does: Generally avoids using an ACE inhibitor and an ARB together, and may consider whether one drug alone or a different medication is a better fit for you. If both are truly needed, they closely monitor your blood pressure, kidney function, and potassium, and may adjust and individualize your doses. What you should do: Keep taking both exactly as prescribed unless you… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "established". Well documented — supported by controlled studies or strong clinical data.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Lisinopril or Candesartan 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 (4)
- Lakhdar R, Al-Mallah MH, & Lanfear DE: Safety and tolerability of angiotensin-converting enzyme inhibitor versus the combination of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker in patients with left ventricular dysfunction. J Card Fail 2008; 14(3):181-188.
- Product Information: Lotensin(R) oral tablets, benazepril HCl oral tablets. Validus Pharmaceuticals LLC (per FDA), Parsippany, NJ, 2014. DailyMed
- Product Information: COZAAR(R) oral tablets, losartan potassium oral tablets. Merck Sharp & Dohme Corp. (per FDA), Whitehouse Station, NJ, 2011. DailyMed
- Product Information: EXFORGE oral tablets, amlodipine valsartan oral tablets. Novartis Pharmaceuticals Corporation (per FDA), East Hanover, NJ, 2019. DailyMed
Keep reading about Candesartan
Keep reading about Lisinopril
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