Molecule

Drug Groups

approved

Description

Eprosartan is an angiotensin II receptor antagonist used for the treatment of high blood pressure. It acts on the renin-angiotensin system in two ways to decrease total peripheral resistance. First, it blocks the binding of angiotensin II to AT1 receptors in vascular smooth muscle, causing vascular dilatation. Second, it inhibits sympathetic norepinephrine production, further reducing blood pressure.

Indication

For the management of hypertension alone or in combination with other classes of antihypertensive agents. Also used as a first-line agent in the treatment of diabetic nephropathy, as well as a second-line agent in the treatment of congestive heart failure (only in those intolerant of ACE inhibitors).

Pharmacology

Angiotensin II, the principal pressor agent of the renin-angiotensin system, is formed from angiotensin I in a reaction catalyzed by angiotensin-converting enzyme [kininase II]. It is responsible for effects such as vasoconstriction, stimulation of synthesis and release of aldosterone, cardiac stimulation, and renal reabsorption of sodium. Eprosartan selectively blocks the binding of angiotensin II to the AT₁ receptor, which in turn leads to multiple effects including vasodilation, a reduction in the secretion of vasopressin, and reduction in the production and secretion of aldosterone. The resulting effect is a decrease in blood pressure.

Toxicity

There was no mortality in rats and mice receiving oral doses of up to 3000 mg eprosartan/kg and in dogs receiving oral doses of up to 1000 mg eprosartan/kg.

Affected Organisms

Biotransformation

Eprosartan is not metabolized by the cytochrome P450 system. It is mainly eliminated as unchanged drug. Less than 2% of an oral dose is excreted in the urine as a glucuronide.

Absorption

Absolute bioavailability following a single 300 mg oral dose of eprosartan is approximately 13%. Administering eprosartan with food delays absorption.

Half Life

The terminal elimination half-life of eprosartan following oral administration is typically 5 to 9 hours.

Protein Binding

Plasma protein binding of eprosartan is high (approximately 98%) and constant over the concentration range achieved with therapeutic doses.

References

External Links