The FDA recently advised health care professionals and consumers not to use a number of dietary supplements found to contain the phosphodiesterase-5 inhibitor sildenafil (Viagra) or an analog of the drug (www.fda.gov). Although the effects of sildenafil may be noticeable (in men), the presence of other, possibly more toxic adulterants in dietary supplements may be more difficult or impossible to detect.Other drugs previously found in dietary supplements have included lovastatin (Mevacor, and others), estrogen, alprazolam (Xanax, and others), indomethacin (Indocin, and others) and warfarin...

Genetic Test for Carbamazepine-Induced Stevens-Johnson Syndrome Carbamazepine (Tegretol, Carbatrol, Equetro, and others), which is now used to treat not only epilepsy but also trigeminal neuralgia and manic episodes in patients with bipolar disorder,1 is a known cause of Stevens-Johnson syndrome (SJS). The incidence of carbamazepine-induced SJS in countries with mainly white populations is 1 to 6 per 10,000 new users of the drug, but Asian patients have a 10-fold higher incidence of this reaction. An association has been found between the human leukocyte antigen (HLA)-B*1502 allele and...

Colesevelam (Welchol - Daiichi Sankyo - Med Lett Drugs Ther 2000; 42:102), a bile-acid sequestrant used to lower LDL cholesterol, has been approved by the FDA as an adjunct to diet and exercise in the treatment of type 2 diabetes. In unpublished studies summarized in the package insert, patients with type 2 diabetes taking metformin (Glucophage, and others), a sulfonylurea or insulin (each as either monotherapy or in combination with other anti-diabetic agents) were given colesevelam 3800 mg per day or placebo; colesevelam significantly reduced glycosylated hemoglobin (A1c) by about 0.5% more...

The US Centers for Disease Control and Prevention (CDC) has reported that measles outbreaks have occurred in New York City, California and Arizona in 2008, and additional cases have been confirmed in Michigan, Wisconsin, Hawaii, New York State, Pennsylvania, Illinois and Virginia (CDC Health Advisory, May 1, 2008). To date, 63 of the 64 infected patients were unvaccinated, and 54 of the cases were associated with importation of the disease. Both measles infection and vaccination (2 doses at least 28 days apart, with the first dose no earlier than 12 months of age) generally provide lifelong...

The May 5, 2008 article (Med Lett Drugs Ther 2008; 50:34) on the approval of natalizumab (Tysabri) for treatment of Crohn's disease in the "Adverse Effects" section on page 35 included the statement: "post-marketing hepatotoxicity, sometimes fatal or requiring liver transplantation, has occurred." Actually, no fatal hepatotoxicity or liver transplantation has been reported to date. The FDA warning about post-marketing hepatotoxicity with Tysabri that was the basis for our statement said: "The combination of transaminase elevations and elevated bilirubin without evidence of obstruction is...

The U.S. Advisory Committee on Immunization Practices has recommended administration of the quadrivalent conjugated polysaccharide meningococcal vaccine (Menactra – Sanofi Pasteur) to all persons 11 to 18 years old, particularly those entering high school and college freshmen living in dormitories.1,2 The peak incidence of meningococcal disease, after early childhood, occurs in the 15-19 year-old age group. The conjugate vaccine is more immunogenic than the meningococcal capsular polysaccharide vaccine (Menommune – Sanofi Pasteur).ADVERSE EFFECTS — The most common adverse reactions with...

The FDA has issued an update (August 18, 2008; www.fda.gov) on occurrences of acute pancreatitis in patients with diabetes taking exenatide (Byetta – Amylin/Lilly). The latest update, which follows an FDA Alert in October 2007, reports 6 cases of hemorrhagic or necrotizing pancreatitis with 2 deaths in patients taking the drug. Whether pancreatitis occurs more often in patients taking exenatide than in patients with diabetes not taking exenatide is not clear.1Given by subcutaneous injection, exenatide is a synthetic peptide that stimulates release of insulin from pancreatic beta cells.2 It...

(Med Lett Drugs Ther 2008; 50:94) In Table 1, "Invasive" should be "less" and "more" rather than "no" and "yes" for CT colonography and colonoscopy, respectively. In the conclusion, CT colonography should be changed to "less invasive" rather than "noninvasive".

The Medical Letter was founded in 1959 by Arthur Kallet, an engineer, and Dr. Harold Aaron, an internist. In 1932, Kallet had written the book 100,000,000 Guinea Pigs, a best-seller that was partly responsible for the Food and Drug Act of 1938, which required for the first time that new drugs show proof of safety. He was the founding director of Consumers Union and started the publication of Consumer Reports. Dr. Aaron, who became the medical director of Consumer Reports, suggested to Kallet that doctors could use a similar publication to evaluate the new drugs that were coming on the market...

(Med Lett Drugs Ther 2009; 51:25) In the paragraph on dosing, the second-to-last sentence should have said that the new recommendations suggest considering use of an alternative antibiotic when the MIC for the infecting organism is ≥2 mg/L, not >2 mg/L.