Vasodilators are widely used for treatment of congestive heart failure (CHF) that has not responded adequately to diuretics and digitalis. Vasodilator drugs redistribute blood volume in patients with heart failure, lowering pressure and reducing volume in the failing left ventricle, which leads to increased cardiac output, decreased pulmonary capillary wedge pressure, and improved exercise tolerance. Since the last Medical Letter review of this subject (Volume 26, page 115, 1984), some additional data have become available.

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.

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).

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.

Perindopril, the tenth angiotensin converting enzyme (ACE) inhibitor to be marketed in the USA, and telmisartan and eprosartan, the fifth and sixth angiotensin receptor blockers, have recently become available for treatment of hypertension.

Some commonly used systemic drugs that may cause pulmonary toxicity are listed in the table below. These adverse effects may sometimes be difficult to distinguish from the underlying disease (JAD Cooper, Jr et al, Am Rev Respir Dis, 133:321, 488, 1986). Pulmonary effects that are part of a generalized reaction or are indirect effects of drugs - on respiratory muscles, for example, or on the immune system - are not included here.

Flosequinan (Manoplax - Boots), a fluoroquinolone derivative, is now available in the USA for treatment of congestive heart failure. Labeling approved by the US Food and Drug Administration recommends the drug only for patients who cannot tolerate or have not responded adequately to an angiotensin-converting enzyme (ACE) inhibitor.

As the weather becomes warmer, physicians may see more photosensitivity reactions due to systemic or topical drugs, perfumes, cosmetics or sunscreens. Even brief exposure to sunlight in warm or cold weather can cause intense cutaneous reactions in patients with drug-induced photosensitivity, and some patients may continue to be sensitive to sunlight long after stopping use of the offending agent.

Ziac (Lederle), a combination of the beta-blocker bisoprolol fumarate and a very low dose (6.25 mg) of the diuretic hydrochlorothiazide, has been approved for treatment of hypertension by the US Food and Drug Administration (FDA). Bisoprolol, a new cardioselective beta-blocker with no intrinsic sympathomimetic activity, has also been marketed as a single drug (Zebeta - Lederle). The manufacturer is promoting the combination for initial treatment of hypertension with the claim that the low doses of the two drugs used together are effective in lowering blood pressure, but are each too low ...