Enalapril/Pimobendan for Dogs

By Molly Price, DVM on Dec. 13, 2023

What Is Enalapril/Pimobendan for Dogs?

Enalapril/pimobendan is a veterinary compounded medication prescribed for dogs that have been diagnosed with mild, moderate, or severe congestive heart failure (CHF) caused by degenerative mitral valve disease (MVD) or dilated cardiomyopathy (DCM).

Enalapril or pimobendan (the active ingredient in Vetmedin®) may be given as individual medications, but they are more commonly used in combination to manage heart disease.

Enalapril is FDA-approved for human use under the brand names Epaned® and Vasotec® and as generic enalapril. Enalapril is currently not FDA-approved as a veterinary medication. However, it is readily utilized in the veterinary field, and veterinarians can legally prescribe certain human drugs in animals in certain circumstances. This is called extra-label or off-label use because this use isn’t described on the drug label.

In certain circumstances, rather than prescribing enalapril and Vetmedin® separately, your vet may recommend a compounded combination formulation of enalapril and Vetmedin®’s active ingredient, pimobendan. This combination preparation is intended for dogs that are already stabilized on the doses of these medications. It is not used in dogs who are initially starting on these medications or for dogs who may need to change dosages.

Compounded medications are prescribed if there’s a specific reason your pet’s health can’t be managed by an FDA-approved drug, such as if your pet has trouble taking pills in capsule form, the dosage strength is not commercially available, or the pet is allergic to an ingredient in the FDA-approved medication.

Compounded medications are not FDA-approved. They are created by either a veterinarian or a licensed pharmacist on an individual basis to best suit a patient’s particular needs. You can learn more about compounded medications here.

Pimobendan is not FDA-approved for human use.

Enalapril/Pimobendan Considerations for Dogs

Treatment with enalapril/pimobendan requires intensive monitoring and close supervision by your veterinarian, particularly if your pet has severe CHF. Before and during your pet’s treatment, your vet may perform blood and urine tests to evaluate the effects of the medications on the liver and kidneys, as well as blood pressure measurement, chest X-rays, and/or an ECG (electrocardiogram).

Enalapril/pimobendan should not be used in pets who are hypersensitive to one or both medications.

Giving enalapril/pimobendan with certain medications can result in health risks to your pet. Always discuss your pet’s medications, including vitamins and supplements, and medical conditions with your veterinarian.

Enalapril should be used with caution in pets with certain medical conditions, such as kidney disease, low sodium level (hyponatremia), diseases that affect blood flow to the brain (cerebrovascular insufficiency), preexisting blood cell abnormalities, skin conditions of collagen and blood vessels such as systemic lupus erythematosus (SLE), and pregnancy.

Pimobendan should be used with caution in pets with uncontrolled cardiac arrhythmias (irregular heartbeats). It is important to note that studies have not been performed to evaluate the safe use of pimobendan in dogs younger than six months of age, dogs with birth defects of the heart, diabetes mellitus, or other serious internal diseases.

How Enalapril/Pimobendan Works in Dogs

Enalapril is classified as an angiotensin converting enzyme (ACE) inhibitor. ACE inhibitors help pets with heart disease by lowering blood pressure and widening blood vessels.

ACE inhibitors block an enzyme that constricts blood vessels in the body. Once that enzyme no longer affects the body, the blood vessels relax and stay open. This decreases blood pressure and allows blood to circulate smoothly in the body.

Pimobendan helps the heart function in two ways. First, it causes vasodilation, which is when the muscles of the blood vessels relax. This allows your dog’s blood vessels to widen for blood to flow more easily.

When veins widen, it reduces the backup of blood that causes abnormal fluid accumulation in the lungs and/or body. The widening of arteries reduces the resistance that the heart pumps against and improves blood flow to organs.

Pimobendan also indirectly acts on the muscle fibers of the heart to improve its ability to contract effectively. This allows the heart to pump blood forward through the heart and increases the volume of blood being moved out of the heart to the rest of the body.

Enalapril/Pimobendan Directions for Dogs

Follow the directions on the drug label or as provided by your veterinarian.

Ask your veterinarian if this medication should be given with or without a meal.

Always provide your pet with plenty of water when they are taking this medication.

Do not stop or reduce your pet’s dose unless instructed to do so by your veterinarian. If your veterinarian recommends that you discontinue this medication for any reason, they will typically recommend that you wean your pet off the medication slowly, and under their supervision.

Missed a Dose?

Speak with your veterinarian about what to do if you forget to give a dose of enalapril/pimobendan. Generally, they may instruct you to give it when you remember, or if it is almost time for your pet’s next dose, to skip the missed dose and resume your normal dosing schedule. Do not give extra or double doses.

Enalapril /Pimobendan Possible Side Effects in Dogs

Side effects of enalapril and pimobendan may include:

Gastrointestinal upset (decreased appetite, vomiting, diarrhea)
Weakness
Lack of coordination
Decreased energy (lethargy)
Low blood pressure (hypotension)
Difficulty breathing
Increased thirst and urination

Human Side Effects

Enalapril is also a prescription medication for humans, frequently with dosages different from those prescribed for your pet by a veterinarian. Due to possible side effects, humans should never use medicine dispensed for their pets and pets should not be given any medicine dispensed for a human’s use.

In humans, enalapril can cause injury and death to a developing fetus. If you are pregnant, trying to become pregnant, or breast-feeding, ensure that you do not ingest this medication, or talk to your veterinarian about the possibility of administering an alternative medication to your pet.

Pimobendan is not approved for use in humans.

If you accidentally ingest this medication, immediately call your physician or the national Poison Control Center hotline at 800-222-1222.

Call Your Vet If:

Severe side effects are seen (see above)
Your pet’s condition worsens or does not improve with treatment
You see or suspect an overdose
You have additional questions or concerns about the use of enalapril/pimobendan

Enalapril/Pimobendan Overdose Information in Dogs

An overdose of enalapril/pimobendan can be serious and requires immediate medical attention. Symptoms of an overdose may include vomiting, fast heart rate (tachycardia), abnormally high blood pressure (hypertension), or abnormally low blood pressure (hypotension) in which a pet may have low energy (lethargy), weakness, fainting (syncope), and collapse.

If you suspect an overdose, immediately contact your veterinarian, seek emergency veterinary care, or call an animal poison control center. Consultation fees often apply.

Pet Poison Helpline (855) 764-7661

ASPCA Animal Poison Control (888) 426-4435

Enalapril/Pimobendan Storage for Dogs

Enalapril/Pimobendan should be stored at controlled temperatures from 68 F to 77 F.

Keep the container tightly closed to protect the medicine from moisture and light.

Keep out of reach of children and pets.

No vet writer or qualified reviewer has received any compensation from the manufacturer of the medication as part of creating this article. All content contained in this article is sourced from public sources or the manufacturer.

Featured Image: Georgijevic/E+ via Getty Images Plus