Matching Articles

The FDA has announced that it is requiring changes in the labeling of the macrolide antibiotic azithromycin (Zithromax, Zmax) to warn about the risk of QT prolongation and cardiac arrhythmias.1 The new warnings are based on a retrospective study in The New England Journal of Medicine (reviewed previously in The Medical Letter2), which found that among patients who received 347,795 prescriptions for azithromycin, there were 29 cardiovascular deaths, a significantly higher rate than the 42 that occurred among patients who received 1,348,672 prescriptions for amoxicillin (which does not prolong...

A reader who took the online continuing medical education (CME) exam for issue 1406 (Med Lett Drugs Ther 2012; 54:101) pointed out that the first question assumed that a rash following oral administration of ampicillin would be due to allergy. Perhaps we should have mentioned in our article on penicillin allergy that late-appearing maculopapular rashes associated with oral ampicillin or amoxicillin are generally considered non-allergic and need not preclude subsequent administration of ampicillin or amoxicillin.

Probiotics are live, nonpathogenic microorganisms (usually bacteria or yeasts) marketed as dietary supplements. They have not been approved by the FDA for any indication. Since our last article on this subject, some new data have become available.

Only a small minority of patients who say they are allergic to penicillin will have a reaction if they take a penicillin.

Antimicrobial prophylaxis can decrease the incidence of postoperative infection, particularly surgical site infection, after some procedures. Recommendations for such prophylaxis are listed in the table that begins on page 74. Antimicrobial prophylaxis for dental procedures to prevent endocarditis was recently discussed in The Medical Letter.

Since 2007, antimicrobial prophylaxis for dental procedures has been recommended only for patients at highest risk of severe consequences from infective endocarditis. There is no indication that more limited use of dental prophylaxis since then has led to an increase in the incidence of infective endocarditis.

A reader suggested that our July 23 article on Drugs for Urinary Tract Infection (Med Lett Drugs Ther 2012; 54:57)1 should have included information on the cost of the drugs we recommended for treatment of acute uncomplicated cystitis.Trimethoprim/sulfamethoxazole DS — Generic formulations are available at large discount pharmacies for $4 for 20 tablets. Trimethoprim/sulfamethoxazole DS is generally found on tier 1 (lowest co-pay) of insurance company formularies.Nitrofurantoin monohydrate/macrocrystals — The wholesale acquisition cost of the generic formulation is about $2.50 per tablet...

The most recent guidelines from the Infectious Diseases Society of America (IDSA) and its European counterpart on the choice of antimicrobials for treatment of uncomplicated urinary tract infections (UTIs) in non-pregnant women focus on the unnecessary use of fluoroquinolones to treat uropathogens that are increasingly becoming resistant to them. Resistance of Escherichia coli to ciprofloxacin in the US has increased from 3% in 2000 to 17.1% in 2010.

Recently published results of a large, carefully conducted retrospective study indicated that use of the antibiotic azithromycin (Zithromax, and others) may increase the risk of cardiovascular death, especially in patients with a high baseline risk of cardiovascular disease.1 One possible mechanism is prolongation of the QT interval, which is known to occur rarely with azithromycin and more frequently with the other macrolide antibiotics erythromycin (Erythrocin, and others) and clarithromycin (Biaxin, and others).Among the patients who received 347,795 prescriptions for azithromycin, there...

The FDA has approved ivacaftor (eye va kaf’ tor; Kalydeco – Vertex) for oral treatment of cystic fibrosis (CF) in patients ≥6 years old with the G551D mutation, which is found in about 5% of patients with CF. It is the first drug approved in the US that treats the cause of the disease.