Benazepril is an ACE inhibitor sometimes sold under the brand names Fortekor or Lotensin. It is used for the treatment of heart failure, high blood pressure, proteinuria (excess protein in urine), kidney failure, and protein-losing glomerulonephropathy in dogs. There is also a study showing that ACE inhibitors like benazepril can help dogs with mitral valve disease and dilated cardiomyopathy (DCM) live longer.

The medicine works by causing blood vessels in the body to widen, allowing for easier blood flow and reducing blood pressure.

Recommended Dosage

Note: ACE inhibitors must be used with caution and only given to dogs who are suitable for treatment. Always seek advice from your vet before giving benazepril to your dog.

Commonly, a dosage of 0.1 – 0.2 mg/lb is used, given once or twice daily. This amount can be used during the treatment of heart failure, high blood pressure, and proteinuria.

A dosage of 0.1 mg/lb can be found on the calculator and chart below.

A chart showing the amount of benazepril used to treat dogs


Dog’s Weight In Pounds: Dosage In Mg:

If your dog loses his appetite or vomits after being given the medicine, you can try giving it with food, but it is best if given on an empty stomach.

Do not stop use of the medicine unless your vet tells you to, and call the vet immediately if you notice an infection or rash developing.

Example: A 50 lb dog would often be prescribed between 0.5 and 1 mg per dose, every 12 to 24 hours.

Can I Give My Dog Benazepril?

Benazepril is safe to give to your dog if it has been prescribed to you by your vet, but could be unsafe for dogs who do not need them.

If your dog suffers with any of the following, he may not be suitable for treatment with ACE inhibitors:

  • A sensitivity to other ACE inhibitors (e.g. enalapril).
  • Obstruction of arteries supplying blood to the brain or a reduced blood supply to the heart.
  • Low levels of sodium.
  • Systemic Lupus Erythematosus (SLE) or other collagen vascular diseases.
  • Abnormalities of the blood.
  • An acute kidney injury.

Dogs with acute kidney injuries may be adversely affected as the medicine can increase the levels of nitrogen compounds in the blood, and decrease the GFR (glomerular filtration rate) – which is basically the rate at which the kidneys filter out waste.

Is it safe to use with other drugs?

Benazepril may be unsafe to use in conjunction with certain medicines, such as aspirin or NSAIDs. For diabetics, it may cause problems by increasing the risk of hypoglycemia.

Pregnancy & Nursing Warning: Benazepril can cross the placenta and is not suitable for treating pregnant animals unless the benefits outweigh the risks. The drug is also present in milk produced by the treated animal – but only in small amounts.

Guidelines For Use

Here are some recommendations for treating your dog safely with this medicine:

  • Never use without veterinary permission.
  • Tell the vet if your dog has suffered bad reactions to other ACE inhibitors.
  • Ask about other possible medicines you could use if your dog has any of the contraindicated conditions mentioned in the previous section.
  • Tell the vet about all medical conditions affecting your dog, and any other medicines he is taking.
  • Before beginning treatment, check hydration status and correct it if necessary.
  • During treatment, monitor blood pressure and perform lab tests regularly.
  • Do not stop use or begin giving your dog other medicines without veterinary permission.
  • Seek veterinary advice if your dog develops symptoms such as rash or infection.
  • Keep in mind that it can take a few weeks to improve your dog’s condition.

Tests which may be performed on your dog every now and then include blood levels of electrolytes, BUN (blood urea nitrogen) and creatinine, and the amount of protein being lost in urine. These tests can help to determine how well your dog’s kidneys are working.

If your dog is being treated for heart failure, symptoms will be monitored carefully for signs of improvement.

What Is It Used For

Benazepril can be used for the following purposes:

  • Chronic kidney failure.
  • Dilated cardiomyopathy.
  • Heart failure.
  • Hypertension.
  • Mitral valve disease.
  • Protein-losing glomerulonephropathy.

There is some discussion within the veterinary community as to whether ACE inhibitors are able to help dogs with ACVIM stage B2 heart diseases (which refers to dogs who show no symptoms but have heart conditions such as enlargement of the heart).

Side Effects


Lethargy is a possible side effect of benazepril, but symptoms relating to GI distress are the most common.

A dog treated with benzepril could experience side effects such as:

Most Common

  • Loss of appetite or vomiting (sometimes remedied by giving the medicine with food).
  • Diarrhea.


  • Lethargy.
  • Low blood pressure.
  • Poor kidney function.
  • Raised levels of potassium.

Benazepril is less likely to cause side effects related to immune reactions (e.g. rashes or low levels of neutrophils/white blood cells) than other similar drugs such as captopril. However, monitor your dog closely for this and report to your vet if you notice infections or rashes, or if signs of GI distress persist.


In case of overdose, ring the ASPCA Animal Poison Control hotline on (888) 426-4435.

Typically, in cases of overdose, blood pressure will be lowered dramatically. Professional veterinary care will be required in such a case, and could consist of saline treatment to return blood pressure to normal. Other symptoms your dog may display include vomiting, rapid heart rate, and tiredness.

Dr. M. Kittleson
Plumb’s Veterinary Drugs