Major Uses

Enalapril is an angiotensin converting enzyme inhibitor, also known as an ACE-inhibitor. This medication is a vasodilator, which means it works to dilate blood vessels in the body. The primary use of enalapril is to treat and sometimes prevent heart failure. It may also be used in the treatment of cardiomyopathy, high blood pressure, and chronic kidney failure.

Enalapril is approved by the Food and Drug Administration for use in dogs. It is also commonly prescribed by veterinarians to treat heart problems in cats.

Common Precautions

Enalapril may cause mild to severe side effects in some animals. The most commonly reported side effects include changes in urination, appetite loss, nausea, and diarrhea. Fever, dizziness, high blood pressure, ulceration of the digestive tract, and fainting have also been reported. In some pets being treated with enalapril, blood pressure can drop too low, causing weakness, lethargy, and listlessness. A change in dose should correct this problem.

In some cases, enalapril may cause elevations in potassium blood levels. The medication may also affect blood supply to the kidneys, potentially leading to kidney failure and death. This adverse effect is most likely to occur in cats being treated with high doses of enalapril and in animals with existing kidney disease.

Enalapril should not be used in animals with impaired kidney function or during pregnancy or lactation. Additionally, kidney function should be tested before, during, and after use. Because enalapril requires conversion to "enalaprilat" by the liver, animals experiencing liver failure should be given an ACE inhibitor that does not require conversion.

Enalapril is known to interact with a number of medications, including non-steroidal anti-inflammatory medications, spironolactone, and furosemide. Enalapril may cause blood potassium levels to become dangerously elevated when used with other drugs that elevate blood potassium levels. Caution is necessary when administering enalapril with insulin, digoxin, methotrexate, corticosteroids, cisplatin, anticoagulants, and some other medications.

Enalapril should not be used in animals with a known allergy or hypersensitivity to the drug. If a known or suspected overdose occurs, a veterinarian should be contacted right away. Symptoms of overdose may include weakness, drowsiness, low blood pressure, kidney failure, or depression.


Enalapril should be stored in its original container, tightly closed, and at room temperature. This medication must be kept away from excess light, heat, and moisture and away from children and pets. It should not be stored in the bathroom or above a kitchen sink.


Enalapril is administered as 1 mg, 2.5 mg, 5 mg, 10 mg, and 20 mg tablets and as an oral liquid. Enalapril may be given with or without food.

The typical dose of enalapril administered to dogs is 0.25 per pound (0.25 to 0.5 mg/kg) once or twice per day by mouth. In cats, the typical dose is 0.12 to 0.25 mg per pound (0.25 to 0.5 mg/kg) once or twice per day by mouth. In cases where enalapril is used in combination with other medications, a lower initial dose may be prescribed. Doses may vary in different species, when the drug is given by a different route or concurrently with other medications, and with regards to a patient's age, breed, and health status. A veterinarian's dosing instructions and/or those printed on the medication label should be followed closely.

If a dose of enalapril is missed, it should be given as soon as possible. If it is almost time for the next scheduled dose of this medication, the missed dose should be skipped. It is important not to give two doses of enalapril at the same time.

In the event of a known or suspected overdose, a veterinarian should be contacted immediately. Symptoms of a potential overdose include weakness, drowsiness, low blood pressure, depression, or kidney failure.

This information is for general reference only and should not be used for the diagnosis or treatment of any condition of your pet. It's intended as a general reference, this information may not include all possible uses, precautions, directions, reactions (including allergic), drug interactions, or withdrawal times. Always consult your local veterinarian and have your pet examined for any advice concerning the diagnosis and treatment of your pet, including which products and doses are most appropriate. Any trademarks are the property of their respective owners. VetDepot is not a pharmacy. All prescription products are dispensed by our Pharmacy Partner. Article last updated 2/2014.