Research finds azithromycin not linked to arrhythmias

Azithromycin, an antibiotic commonly used to treat bacterial infections has been associated with disrupting the heart’s normal rhythm, but a new study has debunked that theory, showing that the drug doesn’t cause ventricular arrhythmias.

The finding comes from researchers in Europe that examined data on nearly 29 million people in Italy, the United Kingdom, Germany, the Netherlands and Denmark.

Results showed that of the 14 million new antibiotic users, 0.1 percent of them developed a ventricular arrhythmias. When compared to amoxicillin, there were no signs of increase risk in arrhythmias in people already using azithromycin.

"Current azithromycin use was associated with an increased risk of ventricular arrhythmia when compared with nonuse of antibiotics, but not when compared with current amoxicillin use. The decreased risk with an active comparator suggests significant confounding by indication," the authors wrote in the study.

However, despite these findings, the study showed there was an increased risk of it in people taking azithromycin compared to people not using antibiotics at all.

"This finding suggests that the risk of ventricular arrhythmia is more likely to be due to a person's poor health and caused by their infection, rather than to azithromycin itself," said Gianluca Trifirò, MD, of the Department of Biomedical and Dental Sciences and Morpho-functional Imaging at the University of Messina in Italy, in a statement. "This finding was confirmed in several sensitivity analyses and replicated in single databases participating in the study."