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).

Eplerenone (e pler' en one; Inspra - Pharmacia), an aldosterone receptor antagonist similar to spironolactone (Aldactone, and others), has been approved by the FDA, but not yet marketed, for treatment of hypertension. It has also been tried for treatment of heart failure.

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.

Mibefradil dihydrochloride (Posicor - Roche), a chemically distinct nondihydropyridine calcium-channel blocker, has been approved by the US Food and Drug Administration (FDA) and is being heavily promoted as the first T-type calcium-channel blocker for treatment of hypertension and chronic stable angina.

Olmesartan medoxomil (Benicar - Sankyo), a substituted imidazole, is the seventh oral angiotensin II receptor blocker (ARB) approved by the FDA for treatment of hypertension.

Treprostinil sodium (tre prost' in il; Remodulin - United Therapeutics), a prostacyclin analogue, has been approved by the FDA for continuous subcutaneous (SC) treatment of patients with pulmonary arterial hypertension who have dyspnea on more than minimal exertion (NYHA Class II-IV).

Several recent case reports suggest that oral sildenafil may be effective for treatment of pulmonary arterial hypertension (PAH). Sildenafil is currently marketed as Viagra for treatment of erectile dysfunction (Medical Letter 1998; 40:51).

Angiotensin receptor blockers (ARBs) are widely used as an alternative to angiotensin converting enzyme (ACE) inhibitors for treatment of hypertension because they lower blood pressure without inducing a cough. It has not been established that they provide the same cardiac benefits as ACE inhibitors. Recently, an editorial in the British Medical Journal suggested that ARBs may increase the risk of myocardial infarction.

Effective treatment of hypertension can prevent organ damage and death. The choice of drugs for initial treatment continues to be controversial.

The FDA has approved Twynsta (Boehringer Ingelheim), a fixed-dose combination of the calcium-channel blocker (CCB) amlodipine and the angiotensin receptor blocker (ARB) telmisartan, for treatment of hypertension.