Pimobendan
4,5-Dihydro-6-[2-(p-methyoxyphenyl)-5benzimidazolyl]-5-methyl-3(2H)pyridazinone
Also known as: Vetmedin · Acardi · Cardisure · Pimocard · Fortekor-Plus · UDCG-115 · Pimobendanum
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
🌎 NA — North America🌍 EU — Europe
Dogs
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Management of the signs of mild, moderate or severe congestive heart failure due to AV valve insufficiency or dilated cardiomyopathy | 0.5 mg/kg total daily dose. Divide daily dose into two portions that are not necessarily equal (using whole and half tablets) and administer approximately 12 hours apart. | PO | Divided q12h | — | 🌎 NA |
| Treatment of congestive heart failure secondary to myxomatous mitral valve disease (MMVD) | 0.4-0.6 mg/kg PO divided twice daily | PO | Divided twice daily | — | 🌎 NA |
| Treatment of heart failure secondary to dilated cardiomyopathy or chronic mitral valve insufficiency | 0.25 mg/kg PO twice daily | PO | Twice daily | — | 🌎 NA |
| General dosing | 0.2-0.6 mg/kg PO divided q12h | PO | Divided q12h | — | 🌎 NA |
| Adjunctive drug for the emergency treatment of CHF (if not overtly critical and a strong positive oral inotrope is needed) | 0.1-0.3 mg/kg PO q12h | PO | q12h | — | 🌎 NA |
| Adjunctive treatment of acute or chronic stage D heart failure (refractory to standard treatment) | 0.3 mg/kg PO to three times daily | PO | Up to TID | — | 🌎 NA |
| Congestive heart failure (MMVD or DCM) / Preclinical DCM / Preclinical MMVD | 0.15 mg/kg | IV | single dose | Single dose, transition to PO 12 hours later | 🌍 EU |
| Congestive heart failure (MMVD or DCM) / Preclinical DCM / Preclinical MMVD | 0.1-0.3 mg/kg | PO | q12h | Lifelong | 🌍 EU |
- Adjunctive treatment of acute or chronic stage D heart failure (refractory to standard treatment): Outside of FDA-approved labeling; requires client consent.
- Congestive heart failure (MMVD or DCM) / Preclinical DCM / Preclinical MMVD: Oral pimobendan can be continued 12 hours after administration of the injection.
- Congestive heart failure (MMVD or DCM) / Preclinical DCM / Preclinical MMVD: Administer 1 hour before food.
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Management of myocardial failure (DCM), especially if not associated with taurine deficiency | 1.25-1.5 mg/cat PO q12hrs | PO | q12h | — | 🌎 NA |
| Heart failure associated with systolic dysfunction (Off-label) | 0.1-0.3 mg/kg | PO | q12h | Lifelong | 🌍 EU |
- Management of myocardial failure (DCM), especially if not associated with taurine deficiency: Off-label use. Little information about clinical efficacy due to rarity of condition.
- Heart failure associated with systolic dysfunction (Off-label): Not authorized (off-label). Pharmacokinetics may differ from dogs. Administer 1 hour before food.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Pimobendan is a highly effective cardiovascular drug classified as an inodilator, meaning it possesses both positive inotropic (increases heart contractility) and vasodilatory properties.
Key Clinical Uses:
- Dogs: Primarily used to treat congestive heart failure (CHF) secondary to dilated cardiomyopathy (DCM) or myxomatous/degenerative mitral valve disease (MMVD). It significantly improves survival times and quality of life compared to traditional ACE inhibitor/furosemide therapy alone. It is considered a first-line therapy for DCM in Doberman Pinschers and is a cornerstone of ACVIM Stage C and D heart failure management.
- Cats: Used off-label for restrictive and dilated cardiomyopathy. It is generally contraindicated in hypertrophic cardiomyopathy (HCM) due to its positive inotropic effects.
Clinical Pearl: While the monograph notes ongoing studies for preclinical use, the landmark EPIC study has since established pimobendan as the standard of care for delaying the onset of heart failure in dogs with preclinical (ACVIM Stage B2) MMVD.
Mechanism of action
Pimobendan exerts its dual inodilator effects through two distinct mechanisms:
- Positive Inotropy (Calcium Sensitization): It increases the sensitivity of the cardiac myofilament Troponin C to intracellular calcium → enhances cardiac contractility. Unlike older inotropes (e.g., digoxin), it achieves this without increasing intracellular calcium levels → no increase in myocardial oxygen consumption.
- Vasodilation (PDE-III Inhibition): It inhibits the enzyme phosphodiesterase III (PDE-III) in vascular smooth muscle → prevents the breakdown of cAMP → ↑ intracellular cAMP → smooth muscle relaxation → mixed arterial and venous dilation. This reduces both cardiac preload and afterload.
Additionally, pimobendan possesses mild antithrombotic activity.
Safety & warnings
Contraindications
- Hypersensitivity to pimobendan
- Hypertrophic cardiomyopathy (HCM)
- Aortic stenosis
- Any condition where augmentation of cardiac output is inappropriate for functional or anatomic reasons
- Any condition where augmentation of cardiac output via increased contractility is not possible anatomically or functionally
Adverse effects
- Poor appetite
- Diarrhea
- Dyspnea
- Azotemia
- Weakness and ataxia
- Pleural effusion
- Syncope
- Cough
- Ascites
- Heart murmur
- Arrhythmias (atrial fibrillation, increased ventricular ectopic beats)
- Worsening mitral valve lesions (acute hemorrhages, endocardial papilloform hyperplasia) with chronic use
- Moderate positive chronotropic effect (tachycardia)
- Vomiting (dose-dependent)
- Reduced appetite or lethargy (rare)
Precautions
Use with caution in patients with uncontrolled cardiac arrhythmias.
Safety has not been evaluated in:
- Dogs younger than 6 months of age
- Dogs with congenital heart defects
- Dogs with diabetes mellitus or other serious metabolic diseases
- Breeding, pregnant, or lactating animals (high doses in lab animals caused increased resorptions)
Note: Patients treated chronically should be regularly examined for worsening mitral valvular lesions and regurgitation.
Drug interactions
Calcium antagonist; attenuates pimobendan-induced increases in cardiac contractility.
Beta-antagonist; attenuates pimobendan-induced increases in cardiac contractility.
Calcium channel blocker; assumed to potentially attenuate positive inotropic effects.
Beta-blocker; assumed to potentially attenuate positive inotropic effects.
Attenuates the positive inotropic effects of pimobendan
Attenuates the positive inotropic effects of pimobendan
Monitoring
- ECG (rate and rhythm)
- Blood pressure
- Echocardiography (cardiac function and valve lesions)
- Clinical signs of heart failure (coughing, exercise intolerance)
- Resting respiratory rate (RRR) at home
- Heart rate and rhythm
- Respiratory rate and effort (Resting Respiratory Rate - RRR)
- Echocardiographic parameters (fractional shortening, left atrial/ventricular dimensions)
- Clinical signs of congestive heart failure
Pharmacokinetics
Half-life
Absorption
Peak levels of parent compound and active metabolite observed 1-4 hours post-dose. Food decreases bioavailability of aqueous solutions (effect on chewable tablets is unknown).
Distribution
Steady-state volume of distribution is 2.6 L/kg. Protein binding of pimobendan and active metabolite in dog plasma is >90%.
Metabolism
Oxidatively demethylated to a pharmacologically active metabolite, which is then conjugated with sulfate or glucuronic acid.
Elimination
Excreted mainly via feces. Clearance is approximately 90 mL/min/kg.
Overdose
Overdoses primarily manifest as cardiovascular signs.
Clinical Signs:
- Tachycardia (dose-dependent increases in heart rate)
- Mild, non-clinical heart murmurs
- Hypotension
Treatment:
- Decontamination: Induce emesis and administer activated charcoal if exposure was recent.
- Monitoring: Continuously monitor heart rate, blood pressure, and ECG.
- Supportive Care: Control hypotension with IV fluids and dopamine if necessary.
Available products
Formulations
- Injectable: 0.75 mg/ml solution
- Oral: 1.25 mg, 2.5 mg, 5 mg, 10 mg flavoured chewable tablets
- Oral: 5 mg hard capsules
- Compound Oral: 1.25 mg pimobendan / 2.5 mg benazepril tablets
- Compound Oral: 5 mg pimobendan / 10 mg benazepril tablets
Veterinary
- Vetmedin Chewable Tablets: 1.25 mg, 2.5 mg, 5 mg
- Vetmedin 0.75 mg/ml injectable solution
- Vetmedin 1.25 mg, 5 mg, 10 mg chewable tablets
- Vetmedin 5 mg hard capsules
- Cardisure 1.25 mg, 2.5 mg, 5 mg, 10 mg flavoured tablets
- Pimocard 1.25 mg, 2.5 mg, 5 mg, 10 mg flavoured tablets
- Fortekor-Plus (pimobendan/benazepril combination tablets)
Human-labeled
- None
Regulatory status
Licensed for preclinical DCM in Dobermanns and preclinical MMVD.
POM-V classification.
No regulatory data for: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store chewable tablets or capsules at room temperature below 25°C (77°F) in a dry place.
Client information
Pimobendan is a medication used to help your pet's heart pump more effectively and to open up blood vessels, reducing the workload on the heart.
- Administration: Give this medication on an empty stomach, ideally one hour before feeding, to ensure it is properly absorbed.
- Strict Schedule: Try to give the doses exactly 12 hours apart as directed by your veterinarian.
- Lifelong Therapy: Pimobendan is a treatment to manage heart failure, not a cure. It is usually required for the rest of your pet's life. Do not stop giving this medication without consulting your veterinarian.
- Monitoring at Home: Watch your pet's breathing rate while they are sleeping (Resting Respiratory Rate). If it consistently rises above 30 breaths per minute, contact your veterinarian.
- Safety: Keep out of reach of children and other animals.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.