Enalapril Maleate



Veterinary: Enacard

Veterinary Availability:

  • Tablets: 1 mg, 2.5 mg, 5 mg, 10 mg, 20 mg


Human: Vasotec

Human Availability:

  • Tablets: 2.5 mg, 5 mg, 10 mg *Note: human-labeled product is not available in the 1 mg tablet.
  • Injectable: Enalaprilat only available for IV use.


An ACE (angiotensin-converting enzyme) inhibitor. Enalapril is converted in the liver to enalaprilat. Both enalapril maleate and enalaprilat are structurally related to captopril. It has a slow onset of action but is of longer duration.

Enalapril/enalaprilat reduces vasoconstriction causing a decrease in peripheral resistance, a decrease in pulmonary vascular resistance and right atrial pressure in the heart. It increases cardiac output, and stroke volume. It has the ability to decrease heart rate. It also has the ability to increase renal blood flow, which may help to preserve renal function by decreasing proteinuria in animals with glomerular disease (Plumb, 2008).

Enalapril is absorbed well orally. However, enalaprilat has poor oral absorption and is best given by IV. They are both poorly distributed into the central nervous system but do cross the placental barrier. Both forms are excreted in urine and feces.


Used in CHF (congestive heart failure), also used with caution in PGN (progressive glomerulonephroses) when hypertension is thought to be a factor.

Drug Interactions or Contraindications

  • Use of NSAIDs with enalapril may reduce its efficacy.
  • Use with caution where azotemia is present.
  • Potential for increased hypotensive effects when used in conjunction with diuretics (e.g., Lasix) or other vasodilators (see Considerations).

Adverse Reactions

CV: hypotension; disturbances in heart rhythm

CNS: sleep disturbances

GI: diarrhea

Renal:  May cause transient increase in BUN and creatinine levels

Blood: neutropenia, agranulocytosis

Skin: itching

Dosage Recommendations

As a vasodilator and adjunctive therapy in heart failure, or in chronic kidney disease to reduce hypertension and decrease high levels of protein in urine:

Initial dose 0.5 mg/kg, PO, BID (may be titrated up based on veterinary discretion to the rat’s response) 12


0.25 mg/lb, PO, BID  3, 12


0.5 mg/kg to 1 mg/kg, PO, q24hr  34, 35, 41, 42, 44


  • Monitor weight. Report weight gain or increased edema to veterinarian.
  • Avoid high sodium, high potassium foods.
  • While using a diuretic (e.g., Lasix), and/or another vasodilator, in conjunction with enalapril can be helpful in heart failure do so with caution due to the potential for increased effect of hypotension.
  • Reports of high doses in rodents may cause maternal and fetal death.
  • Store tablets in tightly closed container at room temperature. Stable for 30 months.


Links to

Linked from


The Rat Guide and its affiliates accept no responsibility for misuse or misunderstanding of its information. This guide in whole or part, exists solely for the purpose of recognizing and understanding the care and illnesses in the pet rat. Please seek advice and treatment from a qualified Veterinarian if your rat is ill.

2000 - 2023 by Karen Grant RN. All rights reserved.
All other written and visual materials used by permission of specific authors for the sole use of the Rat Guide. Please visit our Privacy Policy for details.
Brought to you by KuddlyKorner4u
See Logos page for linking to the Rat Guide.
Contact us here: Rat Guide Team
Please note: Rat Guide email is not checked daily. Send e-mail to if you have an urgent medical problem with your pet rat. When possible, it is always best to take your rat to a qualified rat veterinarian.