FDA Issues Warning About Popular Z-Pak Antibiotics

NEW YORK (CBS News) – The Food and Drug Administration is out with a warning regarding a popular antibiotic.  The FDA says Azithromycin, known as the Z-Pak, can cause a potentially fatal heart problem.

The FDA warns the drug could cause an irregular heart rhythm in some patients that could potentially be deadly.

“The group of patients for whom this warning is most important are those who already have some cardiovascular problem,” said Dr. Wayne Ray of Vanderbilt University’s School of Medicine.

Azithromycin is marketed under the names Z-Pak and Zithromax.  There are also generic versions.

The warning follows a study last May in the New England Journal of Medicine that found the drug had a higher rate of cardiovascular death compared to other antibiotics.

More than 40 million Americans received a prescription for Azithromycin in 2011.  The antibiotic is used to treat many kinds of infections including pneumonia and tonsillitis.
The FDA said doctors should be aware of the risk factors before prescribing the drug to patients.

“Such as a prior heart attack, or angina, or chest pain or people who are known to have abnormalities in their heart rhythm,” said Dr. Ray.

The agency also noted other antibiotics in the same class have the potential for the same problem, so doctors need to consider all the risks.

Pfizer, the company that makes Zithromax, says it continues to monitor the safety of its products and notes that the majority of patients treated with Zithromax are not affected by the new warning on the label.