vetmedin

Pimobendan
(Vetmedin)

Dr. Mark Rishniw, ACVIM

Brand Name: Vetmedin

Available in 1.25 mg and 5.0 mg chewable tablets

Background
Pimobendan is the first drug of a new class of heart medications called inodilators. Studies have shown that when used with other cardiac medications, pimobendan can be effective for dogs with congestive heart failure related to either dilated cardiomyopathy (DCM) or degenerative mitral valve disease (MVD). Veterinary cardiologists are excited about the treatment possibilities of pimobendan and expect it to be commonly used now that it is available in the United States.

This drug differs from other heart medications because it helps the heart pump more efficiently. It opens up the blood vessels that take blood both to and from the heart so the heart doesn’t have to work as hard. It also helps lessen pressure on the heart. Some clinical trials show that dogs who have benefitted from this lived longer than expected. However, more studies are needed to confirm these preliminary results.

Improvements in heart function while on pimobendan have been seen within one week of starting to take the medication, and some dogs continue to show improvement over several weeks. Many owners report an improvement in their pet’s quality of life and well-being. Dogs who show improvement on it will likely remain on pimobendan for the rest of their lives.

According to a study published in the Journal of the American Animal Hospital Association (Lombard CW, Olaf Jöns O, Bussadori CM. 2006 Jul-Aug;42(4):249-61), canine cardiac patients taking pimobendan can gain an extra nine months of life compared to conventional cardiac medications. The study examined 76 dogs with heart failure caused by atrioventricular valvular disease; 31 breeds and five European countries were involved. This same study found that within seven days, half of the dogs no longer had symptoms of heart disease.

Some veterinary cardiologists have used pimobendan for cats with myocardial failure, particularly when the disease is not related to a taurine deficiency, but that is a fairly rare condition in cats. There haven’t been any trials involving cats yet to determine safety, but anecdotally there have not been any obvious safety concerns. Pimobendan is not licensed for use in cats.

In countries where pimobendan has been in use for a long time, pimobendan has become quite popular and is now a first-line treatment for congestive heart failure in dogs with DCM or MVD.

Side Effects
Rarely, dogs taking pimobendan vomit. Call your veterinarian if your dog vomits on this drug.

Interactions with other Drugs
There are no reported drug interactions with pimobendan. However, it is not recommended for use while the dog is taking another PDE inhibitor such as theophylline.

Concerns and Cautions
Pimobendan should not be used in dogs with hypertrophic cardiomyopathy or aortic stenosis.

Pimobendan is not currently recommended for use in dogs with heart disease prior to the onset of congestive heart failure. One study in dogs with early mitral valve disease suggested an increase in valve damage in the dogs given pimobendan. No studies currently exist that show benefit with early use of pimobendan in other heart diseases, such as DCM.

This work was originally published by Veterinary Information Network, Inc. (VIN)
and is republished with VIN's permission.

Vetmedin

UK site. A new heart medication that has now been approved in Europe, Australia, New Zealand, and Canada.

Vetmedin

A discussion of heart failure therapies, and pimobendan's beneficial effects.