Carteolol (Cartrol - Abbott) and penbutolol (Levatol - Reed & Carnrick), two oral beta-adrenergic blocking drugs, were recently approved by the US Food and Drug Administration for once-daily treatment of systemic hypertension. Both drugs are non-selective beta-blockers with mild partial agonist activity. Beta-blockers currently available in the USA for treatment of hypertension are listed in the table on the next page.

Betaxolol (Kerlone - Searle), an oral beta-adrenergic blocker, was recently approved by the US Food and Drug Administration for once-daily treatment of hypertension. The new drug is beta 1 (cardio)-selective with no intrinsic sympathomimetic (partial agonist) activity. It is also available in a topical formulation for treatment of glaucoma (Betoptic - Medical Letter, 28:45, 1986). Beta-blockers currently available in the USA for treatment of hypertension are listed in the table below.

Patients with frequent, severe or disabling migraine headaches may benefit from taking a drug to prevent the attacks. Beta-blockers traditionally have been the prophylactic treatment of choice, but in recent years some antiepileptic drugs such as valproate (Depakote, and others) and topiramate (Topamax) have also been used for this indication. Valproate was approved by the FDA for such use in 1996. Now topiramate has also been approved.

Some classes of drugs include so many agents that hospital formulary committees, managed care organizations and individual practitioners may find it difficult to choose among them. Fifteen beta-adrenergic receptor antagonists (beta-blockers) are now marketed for systemic use in the USA. One or more have been approved by the FDA for use in hypertension and eight other indications.

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.

Changes caused by one drug in the absorption, distribution, metabolism or excretion of another may lead to a pharmacokinetic adverse drug interaction (DN Juurlink et al, JAMA 2003; 289:1652). Additive drug interactions, such as vasodilation caused by both sildenafil (Viagra) and nitrates, can also have adverse effects.

Teniposide (ten i poe' side; VM 26; Vumon - Bristol), an anticancer drug that has been under investigation in the USA for 20 years, has now been approved for use in combination induction treatment of refractory acute lymphoblastic leukemia (ALL) in children. A semisynthetic derivative of podophyllotoxin, teniposide is chemically related to etoposide (VePesid - Medical Letter, 26:48, 1984).

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...