Brands, Medical Use, Clinical Data
Drug Category
- Angiotensin II Type 1 Receptor Blockers
- Antihypertensive Agents
Dosage Forms
- Tablet (400 mg or 600 mg)
Brands / Synonyms
Teveten; Teveten
; Teveten HCT
Indications
For the treatment of hypertension.
Pharmacology
Eprosartan inhibits the pharmacologic effects of angiotensin II. As angiotensin II is a vasoconstrictor, this inhibition effectively lowers blood pressure.
Mechanism of Action
Angiotensin II (formed from angiotensin I in a reaction catalyzed by angiotensin-converting enzyme [kininase II], a potent vasoconstrictor, is the principal pressor agent of the renin-angiotensin system. Angiotensin II also stimulates aldosterone synthesis and secretion by the adrenal cortex, cardiac contraction, renal resorption of sodium, activity of the sympathetic nervous system, and smooth muscle cell growth. Eprosartan blocks the vasoconstrictor and aldosterone-secreting effects of angiotensin II by selectively blocking the binding of angiotensin II to the AT1 receptor found in many tissues (e.g., vascular smooth muscle, adrenal gland). There is also an AT2 receptor found in many tissues but it is not known to be associated with cardiovascular homeostasis. Eprosartan does not exhibit any partial agonist activity at the AT1 receptor. Its affinity for the AT1 receptor is 1,000 times greater than for the AT2 receptor. In vitro binding studies indicate that eprosartan is a reversible, competitive inhibitor of the AT1 receptor.
Absorption
Absolute bioavailability following a single 300 mg oral dose of eprosartan is approximately 13%. Administering eprosartan with food delays absorption.
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.
Biotrnasformation / Drug Metabolism
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.
Contraindications
TEVETEN® Tablets are contraindicated in patients who are hypersensitive to this product
or any of its components.
Drug Interactions
Eprosartan has been shown to have no effect on the pharmacokinetics of digoxin and the pharmacodynamics of
warfarin and glyburide. Thus no dosing adjustments are necessary during concomitant use with these agents. Because
eprosartan is not metabolized by the cytochrome P450 system, inhibitors of CYP450 enzyme would not be expected to
affect its metabolism, and ketoconazole and fluconazole, potent inhibitors of CYP3A and 2C9, respectively, have been
shown to have no effect on eprosartan pharmacokinetics. Ranitidine also has no effect on eprosartan
pharmacokinetics.
Eprosartan (up to 400 mg b.i.d. or 800 mg q.d.) doses have been safely used concomitantly with a thiazide diuretic
(hydrochlorothiazide). Eprosartan doses of up to 300 mg b.i.d. have been safely used concomitantly with
sustained-release calcium channel blockers (sustained-release nifedipine) with no clinically significant adverse
interactions.
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