Z-Pacs deemed suspect by Food and Drug Administration officials

The Food and Drug Administration (FDA) has issued a new warning about the popular antibiotic azithromycin which is sold under brands that include Zithromax and Zmax.

According to new studies, the antibiotic may cause abnormal changes in the electrical activity of the heart that may lead to a potentially fatal irregular heart rhythm.

Patients who are at a higher risk for developing this condition include those with known risk factors such as existing QT interval prolongation, low blood levels of potassium or magnesium, a slower than normal heart rate, or use of certain drugs used to treat abnor...