Enalaprilat

Enalaprilat is an angiotensin-converting enzyme (ACE) inhibitor and the active pharmacological metabolite of the prodrug enalapril. It is used as an injectable medication for the rapid control of blood pressure and for treating congestive heart failure in patients who require parenteral therapy, including hypertensive emergencies. By inhibiting ACE, enalaprilat reduces the formation of angiotensin II and decreases aldosterone secretion, producing vasodilation and reduced sodium and water retention. The increase in bradykinin that accompanies ACE inhibition may contribute to some adverse effects, such as cough and, rarely, angioedema.

Enalaprilat is given intravenously; it is not administered orally because enalaprilat has poor oral bioavailability. The IV formulation provides rapid onset of antihypertensive effect, with duration dependent on dose and renal function. Most of the drug is eliminated by the kidneys; clearance is reduced in renal impairment, requiring dose adjustment.

Common adverse effects include hypotension, dizziness, and hyperkalemia; cough and angioedema can occur but are less frequent than with some other ACE inhibitors. Enalaprilat should not be used in pregnancy and is contraindicated in individuals with a history of angioedema related to ACE inhibitor therapy or with bilateral renal artery stenosis.

Interactions include increased risk of hyperkalemia with potassium-sparing diuretics or potassium supplements, and potential attenuation of antihypertensive efficacy by NSAIDs. Enalaprilat is part of the broader class of ACE inhibitors, which are widely used in cardiovascular and renal diseases.