Enalapril is an ACE inhibitor. ACE inhibitors are antihypertensive drugs that act as vasodilators resulting in the reduction of peripheral resistance. They inhibit angiotensin-converting enzyme (ACE), which is involved in the conversion of angiotensin I to angiotensin II. Angiotensin II stimulates the synthesis and secretion of aldosterone and raises blood pressure via a potent direct vasoconstrictor effect.
Enalapril acts as a prodrug of the diacid enalaprilat, its active form, which is poorly absorbed by mouth. Following oral administration about 60% of a dose of Enalapril is absorbed from the gastro-intestinal tract and peak plasma concentrations are achieved within about 1 hour. Enalapril is extensively hydrolysed in the liver to enalaprilat; peak plasma concentrations of enalaprilat are achieved 3 to 4 hours after an oral dose of Enalapril. Enalaprilat is 50 to 60% bound to plasma proteins. Its elimination is multiphasic but the effective half-life for accumulation following multiple doses of Enalapril is reported to be about 11 hours in patients with normal renal function.
Cardace® is used in the treatment of hypertension and heart failure.
DOSAGE AND ADMINISTRATION:
In the treatment of hypertension: An initial dose of 5mg daily may be given by mouth. The usual maintenance dose is 10 to 20mg given once daily.
For patients with renal impairment: A dose of 2.5mg should be given or to those who are receiving a diuretic.
In the management of heart failure: In patients with heart failure or asymptomatic left ventricular dysfunction, Cardace® is given as an initial dose of 2.5mg daily. The usual maintenance dose is 20mg daily as a single dose or in 2 divided doses. Treatment should be initiated with a low dose under close medical supervision.