Heart disease medicine for dogs: every option compared
Checked against FDA approval records and veterinary references: October 2026
Short answer
Most heart disease in dogs is a leaking mitral valve in smaller breeds or an enlarged, weak heart muscle in larger breeds. Pimobendan (Vetmedin) is the core medicine, and Vetmedin-CA1 is conditionally approved to delay heart failure in dogs with an enlarged heart before symptoms. Once failure develops, furosemide, an ACE inhibitor and spironolactone are added. Counting your dog’s sleeping breathing rate at home catches trouble early.
Heart medicines for dogs at a glance
- Vetmedin-CA1 for the stage before failureWhat it does: Strengthens the heartbeat and opens blood vesselsHow often: Twice a day, about an hour before foodWhat to watch for: Vomiting, diarrhea, reduced appetiteWhere to fill: Vet or veterinary pharmacy
- Human generic diureticWhat it does: Removes fluid from the lungs and body in heart failureHow often: One to three times a dayWhat to watch for: Dehydration, low potassium; kidney blood testsWhere to fill: Regular pharmacy
- TorsemideHuman generic diureticWhat it does: Stronger, longer-acting fluid removal when furosemide is not enoughHow often: Once or twice a dayWhat to watch for: Same as furosemideWhere to fill: Regular pharmacy
- ACE inhibitorsWhat it does: Reduce the heart’s workloadHow often: Once or twice a dayWhat to watch for: Kidney values and potassiumWhere to fill: Regular pharmacy
- SpironolactoneHuman genericWhat it does: Added diuretic that also blocks a hormone that stiffens the heartHow often: Once a day with foodWhat to watch for: High potassium with ACE inhibitorsWhere to fill: Regular pharmacy
| Medicine | What it does | How often | What to watch for | Where to fill |
|---|---|---|---|---|
| Pimobendan (Vetmedin)Vetmedin-CA1 for the stage before failure | Strengthens the heartbeat and opens blood vessels | Twice a day, about an hour before food | Vomiting, diarrhea, reduced appetite | Vet or veterinary pharmacy |
| FurosemideHuman generic diuretic | Removes fluid from the lungs and body in heart failure | One to three times a day | Dehydration, low potassium; kidney blood tests | Regular pharmacy |
| TorsemideHuman generic diuretic | Stronger, longer-acting fluid removal when furosemide is not enough | Once or twice a day | Same as furosemide | Regular pharmacy |
| Enalapril or benazeprilACE inhibitors | Reduce the heart’s workload | Once or twice a day | Kidney values and potassium | Regular pharmacy |
| SpironolactoneHuman generic | Added diuretic that also blocks a hormone that stiffens the heart | Once a day with food | High potassium with ACE inhibitors | Regular pharmacy |
Types and stages
Degenerative mitral valve disease, a leaky valve that causes a murmur, is the most common heart disease in dogs and mainly affects small and medium breeds as they age. Dilated cardiomyopathy, a weakened and enlarged heart muscle, is more common in large breeds. Vets stage heart disease from A, at risk, to D, failure that resists treatment.
Stage B2 is the key point: the heart is enlarged but the dog has no symptoms yet. Treatment with pimobendan at this stage has been shown to delay the onset of heart failure, which is why Vetmedin-CA1 is conditionally approved for it. An X-ray or heart ultrasound tells your vet whether your dog has reached it.
Count the sleeping breathing rate
The earliest sign of fluid building up in the lungs is faster breathing at rest. While your dog is deeply asleep, count breaths for 30 seconds and double it. Your vet will give you a target; a common one is that a rate consistently above 30 breaths a minute should prompt a call. Phone apps can help you keep a record.
Emergency signs
- Labored breathing, breathing with the mouth open at rest, or restlessness and unwillingness to lie down.
- Collapse or fainting.
- Pale, gray or blue gums or tongue.
- A worsening cough with breathing changes.
Living with heart disease
Give heart medicines on schedule and never stop them suddenly. Diuretic doses often change over time, and blood tests check the kidneys and potassium after each change. Avoid salty treats and human food, keep exercise moderate and let your dog set the pace, and keep your dog lean.
Diet and dilated cardiomyopathy
In 2018 the FDA began investigating reports of dilated cardiomyopathy in dogs eating certain diets, many labeled grain-free. It has not established that these diets cause the disease. If your dog has heart disease, ask your vet whether a diet change makes sense.
Keeping the cost down
Furosemide, torsemide, enalapril, benazepril and spironolactone are inexpensive human generics a regular pharmacy can fill with your vet’s prescription. Pimobendan comes through your vet or a veterinary pharmacy, including generic veterinary versions. See which pet medicines a regular pharmacy can fill.
Frequently asked questions
What is the best heart medicine for dogs?
Pimobendan is the core medicine for the most common heart diseases, started before failure in dogs with an enlarged heart. In heart failure it is combined with a diuretic such as furosemide, often with an ACE inhibitor and spironolactone.
What is a normal sleeping breathing rate for a dog?
Most healthy dogs breathe fewer than 30 times a minute while asleep. Your vet will give you a target, and a rate that stays above it should prompt a call.
Can a regular pharmacy fill my dog’s heart medicines?
Furosemide, torsemide, enalapril, benazepril and spironolactone are human generics a pharmacy can fill with your vet’s prescription. Pimobendan comes through your vet or a veterinary pharmacy.
Does grain-free food cause heart disease in dogs?
The FDA investigated reports linking certain diets, many grain-free, to dilated cardiomyopathy but has not established that they cause it. Ask your vet about your dog’s diet.