(May 21, 2012) – The U.S. Food and Drug Administration (FDA) notified healthcare professionals on Thursday regarding a new study published in the New England Journal of Medicine (Azithromycin and the Risk of Cardiovascular Death), reporting a small increase in cardiovascular deaths, and in the risk of death from any cause, in persons treated with a 5-day course of azithromycin (Zithromax, or “Z-Pack”) compared to persons treated with amoxicillin, ciprofloxacin, or no drug.
The New England Journal of Medicine article explains that researchers studied a Tennessee Medicaid cohort designed to detect an increased risk of death related to short-term cardiac effects of medication. The cohort included 347,795 patients who took azithromycin over a five-day period, patients who took amoxicillin, ciprofloxacin, levofloxacin, and those who took no antibiotics.
Zithromax, which is also available in generic form, is generally prescribed to treat bacterial infections of the respiratory system, as well as the urinary tract. The FDA approves the use of Zithromax for:
– acute bacterial infections of the lungs
– acute bacterial sinusitis
– community acquired pneumonia
– some skin infections
– urethritis and cervicitis
– genital ulcer disease
The generic version, azithromycin, belongs to a class of antibacterial drugs called macrolides, which have been associated with cardiovascular effects, specifically, prolongation of the QT interval. (A lengthened QT interval represents ventricular tachyarrhythmias, potentially abnormal heart rhythm problems, and a risk factor for sudden death).
The WARNINGS AND PRECAUTIONS section of the Zmax drug label (azithromycin extended release for oral suspension) was revised in March 2012 to include new information regarding the risk for QT interval prolongation, which appears to be low. The FDA stated that it was currently in the process of updating the risk information in the drug labels for additional macrolide antibiotic drugs.
This research found that “85 of every one million treatment courses of the drug were associated with cardiac death,” which is over twice the death rate as the alternative antibiotic amoxicillin. The FDA said it would communicate any new information on azithromycin and this study or the potential risk of QT interval prolongation after it has completed its review.
Patients taking azithromycin should not stop taking their medicine without talking to their healthcare professional. Healthcare professionals should be aware of the potential for QT interval prolongation and heart arrhythmias when prescribing or administering macrolides.
Zithromax is a Pfizer product, which earned the company $453 million last year.
It seems that if they changed their labels in March, warning of increased risks, they should pull this drug off the shelves until further testing proves its safety. How many more deaths will it take before they take action? What are your thoughts? Will you still fill a prescription for “Z-pack” if your doctor writes you one, or will you request alternative treatment?