Enalapril: veterinary dose and monograph

At a glance

Drug class

Cardiovascular

Also known as

Enacard, Vasotec

Species with doses

Dogs, Cats, Birds, Rabbits, Ferrets, Hedgehogs, Sugar gliders and Primates

General dose range

0.25–0.5 mg/kg PO q12–24h — check the species tables for the indication

Routes

PO

Last reviewed

1 October 2026

Indications

• Canine CHF due to MMVD (ACVIM stage C)
• Canine CHF due to DCM
• Canine protein-losing nephropathy
• Systemic hypertension (dogs and cats)
• Feline CHF (limited evidence)

Enalapril dose by species

Doses are per administration unless stated. mg/kg doses scale with body weight; per-animal, per-quarter and infusion-rate doses are shown as the reference writes them.

Dogs

• CHF (MMVD / DCM): Papich 5e: 0.5 mg/kg q12–24h PO, up to 1 mg/kg/day as 0.5 mg/kg q12h. Plumb’s p.460: 0.5 mg/kg once daily, increased to twice daily if response is inadequate (Enacard label); 0.5 mg/kg twice daily (Kittleson). Recheck creatinine and potassium 5–7 days after starting.
• Protein-losing nephropathy: Plumb’s p.460: glomerular disease 0.5 mg/kg PO q12–24h (Grauer & DiBartola); 0.5 mg/kg once daily, twice daily if proteinuria is not reduced after 2–4 weeks (Vaden); 0.25–1 mg/kg q12–24h (Bartges). Monitor UPC ratio, creatinine and potassium.
• Systemic hypertension: Plumb’s p.460 (Henik 2007): step 1 enalapril or benazepril 0.5 mg/kg q12h; add amlodipine 0.1 then 0.2 mg/kg q24h, spironolactone and hydralazine stepwise if systolic BP stays >160 mmHg after 1–2 weeks. Papich 5e: 0.5 mg/kg q12–24h.

Cats

• CHF / systemic hypertension: Papich 5e: 0.25–0.5 mg/kg q12–24h PO, or 1–1.25 mg per cat per day. Plumb’s p.460: HCM heart failure 1.25–2.5 mg per cat once daily (Kittleson) or 0.25–0.5 mg/kg once daily (Meurs); CKD proteinuria/hypertension 0.25 mg/kg daily up to 0.5 mg/kg twice daily (Polzin). Amlodipine is first-line for feline hypertension; monitor renal values.

Birds

• Heart failure (adjunct): Plumb's p.460: 1.25 mg/kg PO 2–3×/day (Pees 2006); or 0.25–0.5 mg/kg PO q24–48h combined with furosemide (Oglesbee 2009).

Rabbits

• Heart failure / vasodilator: Carpenter's 6th ed (Rabbit cardiovascular table): 0.1–0.5 mg/kg PO q24–48h (or 0.18–0.5 mg/kg PO q12–24h) — monitor for hypotension.

Ferrets

• Dilated cardiomyopathy / CHF: Plumb's p.460 (Williams 2000): start 0.5 mg/kg PO every other day (q48h), increase to once daily if tolerated; dilated cardiomyopathy 0.25–0.5 mg/kg PO q24–48h. Monitor for hypotension — ferrets are sensitive.

Hedgehogs

• Heart failure / vasodilator: Carpenter Exotic Animal Formulary 6th ed, Table 8-7 (p.519): hedgehogs 0.5–1 mg/kg PO q24h. Dilated cardiomyopathy is a recognised disease of pet hedgehogs.

Sugar gliders

• Heart disease (ACE inhibitor): Carpenter Exotic Animal Formulary 6th ed, Table 7-5 (p.501): sugar gliders 0.5 mg/kg PO q24h.

Primates

• Heart failure / hypertension (chimps, marmosets): Carpenter Exotic Animal Formulary 6th ed, Table 13-7 (p.706): chimpanzees 0.3 mg/kg PO/IV q24h; common marmosets 0.5 mg/kg PO q48h; gorilla 0.015–0.125 mg/kg PO q12–24h.

Contraindications

Bilateral renal artery stenosis. Hypotension. Severe aortic stenosis / HCM with outflow obstruction. Pregnancy (teratogenic). Concurrent potassium-sparing diuretics — hyperkalaemia risk. Do NOT use in large animals.

Species-specific warnings

Dogs: Standard for MMVD, DCM, PLN, hypertension. First-dose hypotension if pre-treated with furosemide — start at low dose.

Cats: Often used at 0.25–0.5 mg/kg PO q24h. Cats tolerate ACE-I well but renal function monitoring is essential.

Horses: Not commonly used. Renal function monitoring difficult — extra-label use only.

Cattle: Not used in food-producing cattle.

Adverse effects

• Hypotension (especially first dose)
• Azotaemia / elevated BUN/creatinine
• Hyperkalaemia
• Anorexia, vomiting, diarrhoea
• Weakness, ataxia

Drug interactions

• NSAIDs (meloxicam, carprofen): BLUNT antihypertensive effect + ADDITIVE NEPHROTOXICITY — avoid combination when possible
• Diuretics (furosemide): synergistic in CHF; FIRST-DOSE HYPOTENSION risk — start ACE-I at low dose 1–2 days after furosemide started, monitor BP
• K-sparing diuretics (spironolactone): potential HYPERKALAEMIA — monitor K levels
• Potassium supplements / KCl salt substitutes: hyperkalaemia risk
• Beta-blockers (atenolol, carvedilol): additive hypotension and beneficial bradycardia in CHF
• Pimobendan: SYNERGISTIC for MMVD / DCM — standard combination
• Lithium: reduced lithium clearance (rarely relevant in vet practice)

Pregnancy and lactation

CONTRAINDICATED in pregnancy — fetal ACE-I exposure causes fetal renal failure, oligohydramnios, pulmonary hypoplasia, skull / limb deformities, and stillbirth. FDA Category D (1st tri) / X (2nd-3rd tri). NEVER initiate in pregnant animals; discontinue if pregnancy diagnosed. Excreted in milk in low amounts.

Monitoring

• Renal function (BUN, creatinine) at baseline, 1 week after starting / dose change, then every 3–6 months
• Electrolytes (K+, Na+) — same schedule
• Blood pressure if assessed — target systolic <160 mmHg in hypertensive patients
• Body weight, appetite, respiratory rate at rest — CHF monitoring
• Pregnancy status documented before every prescription in intact females
• Pre-renal azotaemia risk: hydration, NSAID review, volume status
• Hyperkalaemia in renal patients with concurrent spironolactone

Toxicity and overdose

First-dose hypotension — collapse / syncope, especially in volume-depleted or diuretic-pre-treated patients. Pre-renal azotaemia → acute kidney injury in hypovolaemic or stenotic-renal-artery patients. Hyperkalaemia (rare in vet patients, more common with NSAID, K-sparing diuretic, or renal failure). Persistent dry cough (humans — rare in animals due to lower bradykinin response). Hypersensitivity (angioedema rare).

Management: Discontinue. IV fluids for hypotension. Atropine if bradycardia. Vasopressors (norepinephrine 0.1–0.5 µg/kg/min CRI) if refractory hypotension. K correction if hyperkalaemic (calcium gluconate, insulin + glucose, sodium bicarbonate, hemodialysis in severe). Activated charcoal if recent oral overdose. Most patients recover within 24–48 h with supportive care.

Clinical pearls

• MMVD / DCM standard add-on: 0.5 mg/kg PO q24h (dogs), titrate to 0.5 mg/kg q12h if tolerated
• Feline CHF / hypertension: 0.25–0.5 mg/kg PO q24h — cats often need lower starting doses
• Protein-losing nephropathy (PLN): 0.5 mg/kg PO q12h — first-line to reduce proteinuria
• Renal-protective in CKD with proteinuria (UPC >0.5) — even in absence of hypertension
• Quadruple CHF therapy: pimobendan + ACE-I + furosemide + spironolactone
• First-dose hypotension: monitor patient for 4 h after first dose if on diuretics or hypovolaemic
• NEVER with NSAID in dehydrated patient — AKI risk
• Telmisartan (ARB) is an alternative for ACE-I intolerance — different mechanism (AT1 receptor blocker)

Mechanism of action

Angiotensin-converting enzyme (ACE) inhibitor. Pro-drug — hydrolysed in liver to enalaprilat (active metabolite). Inhibits conversion of angiotensin I to angiotensin II → reduces vasoconstriction, aldosterone secretion, and sympathetic activation. Reduces preload (venous capacitance) and afterload (arterial dilation), decreases sodium/water retention, blunts pathological cardiac remodelling. In proteinuric CKD, ACE-I reduces glomerular hyperfiltration via efferent arteriole dilation → renoprotective.

Formulations and products

• Enacard tablet 1 mg
• Enacard tablet 2.5 mg
• Enacard tablet 5 mg
• Enacard tablet 10 mg
• Enacard tablet 20 mg

Storage

Tablets: 15–30 °C, dry, protected from light and moisture. Oral suspension: refrigerated, discard 30 days after reconstitution.

Before you use this dose

Reference doses for veterinary professionals. Confirm the dose against the product label, the patient’s condition, current guidance and local regulations before use; the attending veterinarian remains responsible for every clinical decision.

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• Dobutamine
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• Mexiletine

Frequently asked questions