Current guidelines recommend use of a proton pump inhibitor (PPI) to decrease the risk of gastrointestinal bleeding in patients taking clopidogrel (Plavix) with aspirin. A recent issue of The Medical Letter considered whether omeprazole (Prilosec, and others) or other PPIs could interfere with the antiplatelet effect of clopidogrel. The conclusion was that patients taking both drugs should probably continue to do so until more data became available. Several new publications require reconsideration of that recommendation.

Since The Medical Letter last reviewed the choice of benzodiazepines (Volume 23, page 41, 1981), several new drugs have been marketed and some old ones are now available generically. Most of the benzodiazepines available for oral use in the USA are listed in the table on page 28.

Clozapine (Clozaril - Sandoz), an antipsychotic drug, was first marketed in the USA three years ago (Medical Letter, 32:3, 1990). Because of its hematological toxicity, the US Food and Drug Administration approved the drug only for patients with schizophrenia who cannot tolerate or do not respond to standard antipsychotic drugs.

Cetirizine (Zyrtec - Pfizer), a histamine H 1 -receptor antagonist, has been approved by the US Food and Drug Administration for treatment of seasonal allergic rhinitis, perennial allergic rhinitis and chronic idiopathic urticaria in adults and children more than 12 years old.

Terbinafine (Lamisil - Sandoz), an allylamine synthetic antifungal, previously available in the USA in a topical formulation (Medical Letter, 35:76, 1993) has now been marketed for oral use in the treatment of fungal nail infections caused by dermatophytes. Oral terbinafine has been available in Europe since 1992.

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.

The physiologic changes that occur with aging can affect the pharmacokinetics and pharmacodynamics of many prescription and over-the-counter drugs, increasing the likelihood of adverse effects.

The results of a recently published study suggest that taking the oral direct thrombin inhibitor dabigatran etexilate (Pradaxa) with either simvastatin (Zocor, and others) or lovastatin (Altoprev, and others) increases the risk of major hemorrhage.

Meloxicam, a nonsteroidal anti-inflammatory drug (NSAID) with some cyclooxygenase-2 (COX-2) selectivity in vitro, has been approved by the FDA for treatment of osteoarthritis.

Management of intermittent claudication, the most common symptom of peripheral arterial disease (PAD), involves both risk factor modification and symptomatic treatment (WR Hiatt, N Engl J Med 2001; 344:1608; RM Schainfeld, J Am Board Fam Pract 2001; 14:443).