Quinapril
Prescription ·Exploratory record · not publication-reviewed ·Updated July 13, 2026
Quinapril is an angiotensin-converting enzyme (ACE) inhibitor used to treat hypertension and, as adjunctive therapy, heart failure. It is a prodrug that is hydrolyzed to its active metabolite quinaprilat. By lowering angiotensin II levels it reduces vascular resistance and blood pressure.
Exploratory record, not a reviewed medical publication.
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What the research says.
A quick, data-only summary. The full evidence, dosing, and sources are below.
Quinapril is an angiotensin-converting enzyme (ACE) inhibitor used to treat hypertension and, as adjunctive therapy, heart failure. NutriStack rates the supporting evidence as strong. Common adult dosing is Hypertension: 10-20 mg once daily initially, titrated to 20-80 mg daily in one or two divided doses. Heart failure: 5 mg twice daily initially, titrated to 20-40 mg daily in divided doses., though a prescriber sets the actual dose. With long-term use it can deplete zinc. This profile indexes 3 sources.
The bottom line
Evidence rating strong. Most-documented uses: hypertension, heart failure (adjunctive). 3 sources indexed (2017), with 0 interaction records on file.
How it works, mechanistically.
Core mechanism
Quinapril is a prodrug rapidly de-esterified to quinaprilat, which competitively inhibits angiotensin-converting enzyme (ACE). Blocking ACE prevents the conversion of angiotensin I to the potent vasoconstrictor angiotensin II, lowering systemic vascular resistance and reducing aldosterone secretion, which decreases sodium and water retention. ACE inhibition also slows the degradation of bradykinin, contributing to vasodilation and to characteristic effects such as cough. The net result is reduced blood pressure and decreased cardiac afterload.1,2
Dosing & protocol.
Can be taken with or without food, though a high-fat meal may modestly reduce the rate and extent of absorption. Magnesium- and aluminum-containing antacids and tetracycline can reduce quinapril absorption, so separate dosing by at least 2 hours. Renal impairment prolongs exposure to the active metabolite and warrants dose reduction.2,3
What it depletes.
Nutrients this medication can lower over time, and what to replace.
Zinc
MildACE inhibitors, including quinapril, contain or form sulfhydryl-related chelating chemistry and increase urinary zinc excretion, which over time can lower plasma and tissue zinc concentrations. Chronic ACE-inhibitor therapy has been associated with hyperzincuria and modest reductions in zinc status.
Full safety detail.
Side effects
- Dry persistent cough
- Dizziness
- Headache
- Fatigue
- Hyperkalemia
- Hypotension (especially first-dose)
- Elevated serum creatinine or worsening renal function
- Angioedema (rare but serious)
Contraindications
- History of angioedema related to prior ACE inhibitor therapy2
- Hereditary or idiopathic angioedema2
- Pregnancy (especially second and third trimesters)
- Concomitant use with aliskiren in patients with diabetes
- Concomitant sacubitril/valsartan or within 36 hours of switching
- Bilateral renal artery stenosis (caution)1,2
Sources, by evidence tier.
Numbered references. Citations throughout the page link here.
Reviews & position papers
1- 1Hyperkalemia associated with use of angiotensin-converting enzyme inhibitorsVarious · Clinical pharmacology review · 2017
ACE inhibition reduces aldosterone, decreasing renal potassium excretion and raising hyperkalemia risk; periodic serum potassium and renal function monitoring is recommended.
Reference material
2- 2Accupril (quinapril hydrochloride) Prescribing InformationPfizer · FDA Prescribing Information · 2017
Quinapril lowers blood pressure via ACE inhibition; usual hypertension dose is 10-80 mg daily, with dose reduction in renal impairment and monitoring for hyperkalemia and angioedema.
- 3Effect of an antacid on the bioavailability of quinaprilVarious · FDA Prescribing Information (drug interactions section) · 2017
Coadministration of magnesium/aluminum hydroxide antacids reduces the extent of quinapril absorption; doses should be separated.
Common questions.
Quick answers about Quinapril, drawn from the data on this page.
What is Quinapril?
Quinapril is an angiotensin-converting enzyme (ACE) inhibitor used to treat hypertension and, as adjunctive therapy, heart failure. It is a prodrug that is hydrolyzed to its active metabolite quinaprilat. By lowering angiotensin II levels it reduces vascular resistance and blood pressure.
What is Quinapril used for?
Commonly cited benefits of Quinapril include: Hypertension; Heart failure (adjunctive). NutriStack rates the overall evidence as strong.
What is a typical dose of Quinapril?
A typical adult dose of Quinapril is Hypertension: 10-20 mg once daily initially, titrated to 20-80 mg daily in one or two divided doses. Heart failure: 5 mg twice daily initially, titrated to 20-40 mg daily in divided doses.. The commonly recommended form is Oral tablet. These are general ranges, not personalized advice; confirm the right dose with a clinician.
What are the side effects of Quinapril?
Reported side effects include dry persistent cough, dizziness, headache, fatigue, hyperkalemia, hypotension (especially first-dose). This is educational information; check with a healthcare professional before use.
How strong is the evidence for Quinapril?
NutriStack rates this as Strong, meaning multiple high-quality meta-analyses or systematic reviews converge on the same finding. Full tier criteria are at https://nutristackapp.com/methodology/evidence-tiers.
Use this with your stack
Quinapril in NutriStack.
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