Warfarin sodium (Coumadin, and others) and other coumarin anticoagulants prevent thrombosis, but patient response is highly variable and overanticoagulation can lead to hemorrhage. Genotyping patients for single nucleotide polymorphisms (SNPs) that affect coumarin metabolism and sensitivity may help clinicians estimate the therapeutic warfarin dose. The FDA has added a note to warfarin labeling recommending lowrange doses for patients with such genetic variations. Commercial tests for these variants are now available and cost about $500 per test.

The most common cause of travelers' diarrhea, usually a self-limited illness without fever lasting several days, is infection with noninvasive enterotoxigenic (ETEC) or enteroaggregative (EAEC) strains of Escherichia coli. Campylobacter, Shigella, Salmonella, Aeromonas, viruses and parasites are less common.

Aliskiren (Tekturna - Novartis), the first direct renin inhibitor for treatment of hypertension, has been approved for use in a fixed-dose combination with the diuretic hydrochlorothiazide (Tekturna HCT - Novartis). Many angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) are also available in fixed-dose combinations with hydrochlorothiazide (HCTZ).

The FDA has approved the marketing of the corticosteroid ciclesonide (Alvesco - Sepracor) in a hydrofluoroalkane (HFA) metered-dose inhaler formulation for maintenance treatment of asthma in patients >12 years old. Ciclesonide is also available in the US as a nasal spray for allergic rhinitis (Omnaris), and has been available for asthma in Europe since 2003.

The FDA has approved the marketing of certolizumab pegol (Cimzia - UCB), a tumor necrosis factor (TNF) blocker, for treatment of moderate to severe Crohn's disease refractory to conventional treatment. It is the third TNF blocker approved for this indication.

A recent letter to the editor of the Annals of Internal Medicine documented a single case of myopathy apparently due to an interaction between simvastatin (Zocor, and others) and green tea. Since it became available generically, simvastatin has surpassed atorvastatin (Lipitor) as the best selling statin. As such, it is probably the most common cause of statin-induced myopathy, which is often a result of drug interactions.

Use of screening tests to identify cancers before they cause symptoms can lead to earlier therapy and may improve outcomes. Screening tests for some common cancers are reviewed below.

Some readers have asked whether the widespread practice of taking aspirin to prevent first heart attacks is justifiable and, if so, what the dose should be. Only one large well-designed study has tested the use of aspirin for this purpose.

Patients may be asking about Airborne, a dietary supplement that is being heavily promoted for prevention and treatment of colds. It contains 7 herbal extracts, 3 vitamins, 2 amino acids, selenium, zinc and many other ingredients. Airborne Jr is available for children. There are some concerns. First, there is no conclusive evidence that this product or any of its ingredients prevents colds or shortens their duration. Second, the adult tablet contains 1 g of vitamin C, and the directions for use advise taking 1 tablet at the first sign of a cold and repeating the dose every 3 hours as...

Health Canada, the Canadian equivalent of the FDA, recently issued a public advisory about postmarketing reports of myalgia, rhabdomyolysis, hepatitis, pancreatitis and thrombocytopenia associated with use of ezetimibe (Zetia in the US; Ezetrol in Canada). Ezetimibe is often added to a statin to increase LDL cholesterol lowering (Drugs for Lipids, Treat Guidel Med Lett 2005; 3:15). The advisory did not specify whether these patients were also taking a statin, but according to the Canadian manufacturer Merck Frosst/Schering (Merck/Schering-Plough in the US), some of the patients who developed...