Captopril

Prescription ·Exploratory record · not publication-reviewed ·Updated July 13, 2026

Captopril is a short-acting, orally active angiotensin-converting enzyme (ACE) inhibitor used to treat hypertension, heart failure, left ventricular dysfunction after myocardial infarction, and diabetic nephropathy. It was the first ACE inhibitor brought to market and contains a sulfhydryl group that distinguishes it from later agents. Because of its short half-life it is typically dosed two to three times daily, and it is taken on an empty stomach since food reduces its absorption.

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Publication status

Exploratory record, not a reviewed medical publication.

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This generated database record has not completed a claim-level review by a qualified human medical reviewer. Bibliography links and evidence labels are not approval. The page remains available for reference and is excluded from search indexing.

In short

What the research says.

A quick, data-only summary. The full evidence, dosing, and sources are below.

Captopril is a short-acting, orally active angiotensin-converting enzyme (ACE) inhibitor used to treat hypertension, heart failure, left ventricular dysfunction after myocardial infarction, and diabetic nephropathy. NutriStack rates the supporting evidence as strong. Common adult dosing is Hypertension: 25 mg to 50 mg two to three times daily, titrated to a usual maximum of 150 mg per day. Heart failure: typically started at 6.25 mg to 12.5 mg three times daily and titrated toward 50 mg three times daily as tolerated., though a prescriber sets the actual dose. With long-term use it can deplete zinc. This profile indexes 3 sources.

What it's good for

Hypertension²
Heart failure with reduced ejection fraction²
Left ventricular dysfunction after myocardial infarction²
Diabetic nephropathy with proteinuria²

What to watch for

Dry persistent cough
Hyperkalemia (elevated blood potassium)
Hypotension, especially after the first dose
History of angioedema related to prior ACE inhibitor use
Hereditary or idiopathic angioedema

The bottom line

Evidence rating strong. Most-documented uses: hypertension, heart failure with reduced ejection fraction, left ventricular dysfunction after myocardial infarction. 3 sources indexed (1998–2012), with 0 interaction records on file.

The science

How it works, mechanistically.

Core mechanism

Captopril competitively inhibits angiotensin-converting enzyme (ACE, kininase II), preventing the conversion of angiotensin I to the potent vasoconstrictor angiotensin II. The resulting fall in angiotensin II reduces vasoconstriction and lowers aldosterone secretion, decreasing sodium and water retention while promoting potassium retention. Reduced ACE activity also slows the breakdown of bradykinin, contributing to vasodilation and to the characteristic dry cough. The net effect is lowered systemic vascular resistance and blood pressure, with reduced cardiac afterload that benefits patients with heart failure.^2,3

Class

ACE Inhibitor

Absorption

Best on an empty stomach

Dosing

Dosing & protocol.

Common range

Hypertension: 25 mg to 50 mg two to three times daily, titrated to a usual maximum of 150 mg per day. Heart failure: typically started at 6.25 mg to 12.5 mg three times daily and titrated toward 50 mg three times daily as tolerated.

Recommended form

Oral tablet

Food reduces the absorption of captopril by roughly 30 to 40 percent, so it should be taken at least one hour before meals to ensure consistent bioavailability.

Depletions

What it depletes.

Nutrients this medication can lower over time, and what to replace.

Zinc

Moderate

Captopril contains a sulfhydryl (thiol) group that chelates zinc, forming a captopril-zinc complex that increases urinary zinc excretion. Chronic ACE inhibition with sulfhydryl-containing agents can lower plasma and cellular zinc concentrations, and zinc loss has been implicated in taste disturbances (dysgeusia) reported with the drug.

Replace ZincMonitor Serum or plasma zincOnset Weeks to months of continuous therapy

Full Captopril depletion and interaction guide →

Safety

Full safety detail.

Side effects

Dry persistent cough
Hyperkalemia (elevated blood potassium)
Hypotension, especially after the first dose
Dizziness and lightheadedness
Loss or alteration of taste (dysgeusia)
Skin rash
Elevated serum creatinine or reduced kidney function
Angioedema (uncommon but potentially serious)
Neutropenia or agranulocytosis (rare, more likely with renal impairment or collagen vascular disease)

Contraindications

History of angioedema related to prior ACE inhibitor use
Hereditary or idiopathic angioedema
Pregnancy, particularly the second and third trimesters
Bilateral renal artery stenosis¹
Concomitant use with aliskiren in patients with diabetes
Known hypersensitivity to captopril or other ACE inhibitors^2,3

Sources

Sources, by evidence tier.

Numbered references. Citations throughout the page link here.

Reviews & position papers

1Mechanisms and clinical relevance of ACE inhibitor associated hyperkalemiaPalmer BF · New England Journal of Medicine · 2004
Reduced aldosterone secretion from ACE inhibition impairs renal potassium excretion, and combining these drugs with potassium supplements or potassium-sparing agents markedly raises hyperkalemia risk.

Reference material

2Capoten (captopril) Prescribing InformationU.S. Food and Drug Administration · FDA Label · 2012
Captopril is indicated for hypertension, congestive heart failure, left ventricular dysfunction after myocardial infarction, and diabetic nephropathy, with food reducing absorption by 30 to 40 percent.
3Effect of captopril on zinc metabolism and taste acuityGolik A, et al. · Journal of the American College of Nutrition · 1998
Captopril, which contains a sulfhydryl group that chelates zinc, has been linked to increased urinary zinc loss and to dysgeusia, a recognized side effect of the drug.

FAQ

Common questions.

Quick answers about Captopril, drawn from the data on this page.

What is Captopril?

What is Captopril used for?

Commonly cited benefits of Captopril include: Hypertension; Heart failure with reduced ejection fraction; Left ventricular dysfunction after myocardial infarction; Diabetic nephropathy with proteinuria. NutriStack rates the overall evidence as strong.

What is a typical dose of Captopril?

A typical adult dose of Captopril is Hypertension: 25 mg to 50 mg two to three times daily, titrated to a usual maximum of 150 mg per day. Heart failure: typically started at 6.25 mg to 12.5 mg three times daily and titrated toward 50 mg three times daily as tolerated.. 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 Captopril?

Reported side effects include dry persistent cough, hyperkalemia (elevated blood potassium), hypotension, especially after the first dose, dizziness and lightheadedness, loss or alteration of taste (dysgeusia), skin rash. This is educational information; check with a healthcare professional before use.

How strong is the evidence for Captopril?

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

Captopril in NutriStack.

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