Irbesartan (Avapro - Sanofi/Bristol-Myers Squibb) is the third angiotensin II receptor antagonist to become available in the USA for oral treatment of hypertension. Losartan (Cozaar) and valsartan (Diovan) were marketed earlier. Eprosartan (Teveten - SmithKline Beecham) has been approved by the FDA but not marketed.

Valsartan (Diovan - Novartis), a non-peptide tetrazole, is the second angiotensin II receptor antagonist approved for oral treatment of hypertension by the US Food and Drug Administration. The first was losartan (Cozaar - Medical Letter, 37:57, 1995).

Losartan potassium (Cozaar - Merck), the first angiotensin II receptor antagonist, has been approved for oral treatment of hypertension by the US Food and Drug Administration. It will be marketed both alone and in a fixed-dose combination with the diuretic hydrochlorothiazide (Hyzaar).

Moexipril hydrochloride (Univasc - Schwarz Pharma), an angiotensin-converting enzyme (ACE) inhibitor, was recently approved by the US Food and Drug Administration (FDA) for treatment of. It is the eighth ACE inhibitor to be marketed in the USA.

Trandolapril (tran doe la pril; Mavik - Knoll) has become the ninth angiotensin-converting- enzyme (ACE) inhibitor to be approved by the US Food and Drug Administration (FDA) for treatment of hypertension.

Doxazosin (mesylate - Roerig), an alpha1-adrenergic receptor blocker similar to prazosin (Minipress, and others) and terazosin (Hytrin), was recently approved by the US Food and Drug Administration for treatment of hypertension.

The importance of adequate control of hypertension in preventing organ damage and death is well established, but the choice of drugs is still controversial. Three recent drug trials, one supporting initial therapy with a diuretic, the second favoring an angiotensin converting enzyme (ACE) inhibitor, and the third showing equivalence between a calcium-channel blocker and an angiotensin-receptor blocker (ARB) have intensified the debate.

Carvedilol (Coreg - SmithKline Beecham and Boehringer-Mannheim), a betaadrenergic and alpha-adrenergic blocker approved by the FDA for treatment of hypertension in 1995, but not marketed at that time, has now been approved and marketed for treatment of mild or moderate (NYHA class II or III) heart failure stabilized on other drugs. It is being promoted as an add-on drug that reduces the morbidity and mortality of the disease.

Nebivolol (Bystolic - Forest) is a new beta-blocker that has been approved by the FDA for treatment of hypertension. It has been marketed in Europe since 1999 for treatment of hypertension and heart failure.

View the Comparison Chart: Some Drugs for Irritable Bowel Syndrome with Constipation (IBS-C)