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.

Finasteride (Proscar - Merck) has now been approved by the US Food and Drug Administration (FDA) for oral treatment of benign prostatic hyperplasia. A 4-aza-steroid, the drug is a specific inhibitor of steroid 5 -reductase, the enzyme that catalyzes conversion of testosterone to dihydrotestosterone. Dihydrotestosterone is required for development and maintenance of prostatic hypertrophy (JS Tenover, Endocrinol Metab Clin North Am, 20:893, 1991).

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.

Terazosin (Hytrin - Abbott), a postsynaptic alpha 1 -adrenoreceptor blocker previ-ously available for treatment of hypertension (Medical Letter, 29:113, 1987), has now been approved by the US Food and Drug Administration (FDA) for treatment of benign prostatic hyperplasia (BPH). Although not previously approved by the FDA, terazosin and other alpha-blockers such as prazosin (Minipress, and others) or doxazosin (Car-dura) have been used for this indication for many years.

Many commonly used drugs can interfere with sexual function in both men and women, causing loss of libido, interfering with erection or ejaculation in men, and delaying or preventing orgasm in women. Drug-related effects on sexual function may be difficult to distinguish from the effects of depression or disease, but most are reversible when drug use is stopped and sometimes when dosage is decreased. Since many patients are reluctant to talk about sexual difficulties, physicians may wish to ask about the possibility of drug-induced sexual dysfunction, particularly when they have...