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Vetmedin Killed My Dog, But The Truth Is Not That Simple

Vetmedin Killed My Dog, But The Truth Is Not That Simple

Heart diseases in dogs are not uncommon, and some dog breeds, like Doberman Pinschers, are more prone to them. While it is an FDA-approved drug, some side effects in dogs can be fatal, with owners saying Vetmedin killed my dog.

Underlying conditions or allergic reactions can have a negative impact on dog health, so make sure your veterinarian is aware of your dog’s entire body condition before prescribing Vetmedin therapy.

Still, there are scenarios where adverse reactions happen, and you might be worried that your dog’s heart med treatment could be fatal. In this article, we will go through how this medication works, what condition it is used for, and its possible side effects.

Can Vetmedin Actually Kill My Dog?

White medical pills and tablets spilling out of a drug bottle

This drug is used for treating a number of heart conditions in dogs, such as congestive heart failure (CHF), mitral valve disease (MVD), and dilated cardiomyopathy (DCM). Its main role is to strengthen the heart muscle and improve blood flow by widening blood vessels.

Pimobendan is the active ingredient in Vetmedin, and the effect it has is great for treating CHF that occurs due to an atrioventricular valvular insufficiency (AVVI) or dilated cardiomyopathy (DCM). If your dog has a heart murmur or an enlarged heart, Vetmedin will work well for both.

Still, it is important to note that plenty of other heart conditions can be exacerbated and potentially fatal if Pimobendan is used. So, why use it if it can kill your dog?

Well, one of the most authoritative studies related to CHF and Pimobendan treatment, the EPIC study, showed that it helped dogs that did not yet develop one of the relevant heart conditions but were predisposed to them.

This EPIC study was the proof veterinarians needed to explain to owners that the phrase Vetmedin killed my dog is false — the wrong treatment and dosage or underlying conditions killed their dog.

A cardiologist will determine if Vetmedin is appropriate according to the specifics of the condition. Any heart diseases that involve an increased heart rate are not candidates for pimobendan as it increases the heart’s strength, which would result in death.

Vetmedin will not just kill your dog without warning signs. Vetmedin toxicity is

Vetmedin Side Effects And Toxicity

Though heart medications such as benazepril and pimobendan have side effects, when prescribed based on a sound diagnosis, they have minor contraindications.

Sudden death is not a frequent side effect of Vetmedin and is, in most cases, a result of an incorrect diagnosis or an allergic reaction. Dog owners should be aware that their beloved dog will not be poisoned by pimobendan but will have serious adverse effects if used inappropriately.

On the topic of pimobendan toxicity, administering this drug to a healthy dog or one with an increased heartbeat can result in death.

Side effects in dogs who are correctly put on Vetmedin therapy include tachycardia, gastrointestinal complications (loss of appetite, diarrhea), seizures, or elevated hepatic enzyme.

Behavioral changes, such as lethargy, dizziness, or confusion, are also possible but with a low rate of occurrence. If you notice any of the above symptoms while your dog is on Vetmedin, rush it to the DVM or animal hospital.

The side effects that lead to death are, again, better with pimobendan than benazepril, so choosing the latter as an alternative for DCM or AVVI-induced CHF is not recommended based on side effects.

How Much Vetmedin Is Toxic To Dogs?

Welsh corgi pembroke sick dog receiving a medifaction in a pill

The medical term for Vetmedin poisoning is pimobendan toxicosis. In a study that aimed to determine clinical signs, treatment, and recovery chances of pimobendan toxicosis, most dogs reacted positively to treatment.

Dogs who ingested 2.6mg/kg of pimobendan were considered candidates for the study, with the upper limit being 21.3mg/kg.

Symptoms included intense tachycardia, hypotension, and hypertension. However, some dogs did not display symptoms at all. Treatment for the latter involved active charcoal and emesis, while symptomatic dogs relied on IV fluid administration and supportive care.

Asymptomatic dogs can display non-medical symptoms that include behavioral changes such as lethargy, confusion, circling, erratic behavior, etc. However, there is no scientific data confirming the direct correlation of pimobendan toxicosis to these clinical signs.

In What Form Does Vetmedin Come?

Pet owners will be delighted that Vetmedin comes in dog-friendly shapes that are easy to administer. You have the choice of feeding a chewable tablet of Vetmedin to your angry Chihuahua or going the standard pill route.

Although the tablet form is still most frequent for commercial purposes, Vetmedin has been adapted for animal consumption, especially for dogs and cats. You can find the beef-flavored chewable tablet on the Chewy website, among others.

Alternative Meds For DCM And AVVI-Induced CHF

Though there are alternatives to Vetmedin therapy, their efficacy is not considered worth the switch. In dogs that have diagnoses of conditions that are effectively treated by Pimobendan, there is no alternative FDA-approved med.

If you researched Vetmedin, you definitely came across benazepril, which is commonly used for a variety of conditions, such as heart failure, kidney disease, and high blood pressure. Simply put, it is an angiotensin-converting enzyme or ACE inhibitor.

Its wide spectrum of application means it will not be as good as Vetmedin for CHF caused by DCM o AVVI, but the side effects are mostly non-fatal.

Keep in mind that only dogs with conditions that are not suitable for pimobendan and those allergic to its pharmacology can have fatal outcomes as side effects. A correct diagnosis and test period while on Pimobendan are key for avoiding such complications.

Another study called QUEST, which stands for Quality of Life and Extension of Survival Time, showed that pimobendan was superior to benazepril in terms of lifespan after CHF had been diagnosed.

What Is Pimobendan And How It Works

dog hearts mold, normal heart and heart with DCM

Commercially known as Vetmedin, Pimobendan is a positive inotropic. It works by increasing the quantity of intracellular calcium at the muscle’s disposal. Since the heart is a muscle, the increased sensitivity of contractile proteins to calcium makes it pump harder.

Stronger heart wall contraction means blood is pushed with a bigger force, allowing it to reach every blood vessel in the body more quickly. Dogs that have problems with blood supply to distant capillaries benefit most from this.

Another effect of Pimobendan is vasodilation, or the widening of blood vessels. The wider the diameter of the blood vessel, the larger the volume of blood pushed through it.

These two main effects of the med make it an ideal choice for atrioventricular valvular insufficiency and dilated cardiomyopathy, which is why it is the most frequently used drug for preventing the onset of the conditions in dogs with the predisposition.

It is also excellent as a way to prolong life expectancy in dogs that already have one of these conditions diagnosed. To better understand to what extent this is true, let me explain the EPIC study and its results.

Breakdown Of The EPIC Study Results

First off, there were two groups of dogs tested in this study — those who were administered placebo therapy and a group that took Pimobendan.

A total of three hundred fifty-nine dogs were split into a one hundred seventy-nine group using pimobendan, while one hundred eighty dogs were on placebos.

The results were strongly in favor of the pimobendan group, showing that as many as double the number of dogs on Pimobendan compared to the ones on placebo did not show signs of a primary endpoint (onset of DCM or AVVI).

For dogs that were put on Pimobendan and placebos with either condition already diagnosed, the life expectancy was extended by sixty percent. That means dogs on Pimobendan with DCM or AVVI lived fifteen months more than those on the placebo.

Such conclusive results forced the study to be stopped in order to give all the dogs the best possible chance of living longer with the diagnosis or delay the primary endpoint.

A Closer Look Into The Heart Diseases Vetmedin Is Good For

Veterinary team for treating sick Golden Retriever

Since Vetmedin is a drug administered only for specific heart conditions, you should know more about them to help your pet live the longest possible life.

Most of them are congenital, and these heart diseases, or rather your dog’s predisposition to them, can be discovered through DNA tests most frequently performed on the puppy’s parents.

For dogs that are predisposed to CHF, DCM, or AVVI, such as Chihuahuas and Doberman Pinschers, parent health screens can provide information on what to expect. For dogs with established diagnoses, Vetmedin can add fifteen months to the life expectancy without pimobendan.

Congestive Heart Failure (CHF)

This condition can be described by a reduced capacity of the heart to push blood to all blood vessels, which results in fluid accumulation in the abdomen. This fluid buildup is known as ascites or abdominal effusion.

Similar to human heart anatomy, the dog’s heart consists of two sides. The left side, or left ventricle, has the job of redirecting unoxygenated blood to the lungs, while the right ventricle receives the oxygenated blood and pumps it back into the body.

Following the basic anatomy of the heart, two main types of CHF exist, left-sided CHF and right-sided CHF. The former indicates that the blood that was already oxygenated is pushed back into the left atrium, creating an overflow into the lungs.

Left-sided CHF causes pulmonary edema, with the most common symptoms being a persistent cough and difficulty breathing.

Right-sided CHF, on the other hand, means that the unoxygenated blood spills back into the right atrium and is pushed through the body. This means that congestion will occur due to the low levels of oxygen in the “fresh” blood, with ascites or peripheral edema for symptoms.

To treat the ascites, dogs are usually put on furosemide. This drug is a diuretic, which means your body will try to get rid of the fluid buildup by excreting it through urine.

Pulmonary edema is also treated by diuretics, but other meds, like antibiotics or NSAIDs, are viable in scenarios where infection or inflammation is present as a secondary condition.

Atrioventricular Valvular Insufficiency

Sick Beagle Puppy is lying on dog bed

The most frequent cause of CHF is atrioventricular valvular insufficiency. Eighty percent of dogs with CHF have AVVI as the cause, but there are other causes of CHF in dogs — mitral valve disease and dilated cardiomyopathy.

Atrioventricular valvular insufficiency (AVVI) is generally a congenital heart condition that affects the ability of the mitral valve to properly close the passage between the left atrium and left ventricle.

The blood that spills back into the ventricle can cause ascites, heart murmur, coughing, panting, or hypoxia. The treatment usually consists of managing the symptoms with diuretics, NSAIDs, and antibiotics if there is inflammation/infection. Vetmedin is used for the treatment of CHF itself.

Additionally, high-intensity exercise has to be put on hold during therapy. Your vet will probably advise adapting the diet to the dog’s condition by lowering sodium intake, but regardless of that, the chances of survival are low.

Mitral Valve Disease

This heart disease has the same symptoms as AVVI, but its origin is not congenital. A “leaking” mitral valve will create the same problems as one that was genetically malformed, but the causes are external in most cases.

Bacterial and fungal infections can often spread into the bloodstream and infect the heart valve. This is known as endocarditis and is treated with antibiotics or antifungal meds, depending on the type of infection.

One of the most common origin points of endocarditis is periodontal disease. Untreated mouth infections can easily enter the blood and spread throughout the body.

Another possible cause can be ruptured cords that attach the two leaflets of the valve. If your dog has a heart murmur, MVD will be the most frequent diagnosis.

Small dog breeds are much more prone to this condition, and the most affected are Chihuahuas, Shih Tzu, Cocker Spaniels, Dachshunds, Miniature Schnauzers, and Pomeranians.

Early diagnosis will definitely help your dog live to see another year or more if treatment is administered immediately. Advanced cases of MVD have grim prognoses, so spotting the symptoms quickly is essential.

Lifelong medications like inotropes, beta-blockers, vasodilators, etc., will be necessary. Though not all of the drugs will be used at the same time, most cases will involve Vetmedin.

Dilated Cardiomyopathy

Young happy veterinary nurse smiling while playing with a dog.

Dilated cardiomyopathy is the thinning out of the heart’s wall. If a dog has an enlarged heart, that means that the walls of the heart have been thinned out and stretched so that the organ itself becomes too large for the body.

Specifically, the lower heart chambers expand, compressing the thickness of the ventricle walls against themselves. The atria can also be enlarged, but it is a much rarer occurrence.

Common symptoms include difficulty breathing, lethargy, weakness, restlessness, and coughing. Diagnosing DCM is a complicated process and will involve several tests to confirm the diagnosis.

The vet will probably listen to your dog’s heart to try and hear any anomalies, followed by a full blood panel, urine test, chest X-ray, electrocardiogram, echocardiogram, and optionally a holt that will monitor your pet’s heart rate in case the cardiologist suspects arrhythmia.

Treating it is equally challenging as therapy can consist of a combination of diuretics, ACE inhibitors, vasodilators, etc. For Doberman Pinschers, the diagnosis of DVM usually means only a few months of life after confirmation.

Many other breeds or even individual dogs react much better to therapy and live anywhere from half a year to two years after a positive DVM diagnosis.

Vetmedin has been proven to reduce the size of the heart, in addition to being efficient as a vasodilator too, so it covers many of the symptoms while delaying the onset of congestive heart failure.


Hopefully, you are among those whose dog was not killed by a misdiagnosis or pimobendan toxicosis. Congestive heart failure is a heart disease that requires the use of many diagnostic tools, and you should choose a vet that is experienced in that.

Because a cardiologist will have the final say, make sure it is a board-certified specialist. Adequate treatment will depend upon a correct diagnosis.

All of the diseases we went through, except CHF, are at the same time the causes of it, which means Vetmedin (pimobendan) will help delay the onset of congestive heart failure. Even if it is diagnosed, therapy should give you several months or even years of hanging out with your dog.

In case you notice any symptoms relating to the previously mentioned conditions, take your dog to the vet or animal hospital. Regular check-ups are crucial for spotting conditions that can be asymptomatic for a while, such as DCM.

Breeder choice will be your first barrier to avoiding CHF and other heart-related anomalies. You should always ask for your puppy’s parents’ DNA tests that rule out hereditary genetic diseases before getting a puppy. Health guarantees are a sign of a good breeder in most cases.

Forget about Vetmedin killed my dog scenarios. The drug’s use has been proven, and the only thing that can cause your dog’s death in regard to pimobendan treatment is human error.

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