Fluoroquinolone is an antibiotic drug used to treat and prevent various bacterial infections. Some common fluoroquinolone antibiotics include ofloxacin, levofloxacin, gemifloxacin, and ciprofloxacin. But recent studies have suggested that using oral fluoroquinolone may be associated with a higher risk of arrhythmia. This study aims to evaluate the risk of serious arrhythmia associated with the intake of oral fluoroquinolone.

This bi-national cohort study examined a total of 909,656 courses of fluoroquinolone aged 40-79 years. The fluoroquinolones included in the study were ciprofloxacin 82.6%, norfloxacin 12.1%, ofloxacin 3.2%, moxifloxacin 1.2%, and other fluoroquinolones 0.9%). 909,656 courses of penicillin were matched in a 1:1 ratio. The primary outcome of the study was the risk of serious arrhythmia.

A total of 144 cases of serious arrhythmia were reported during the follow-up. Sixty-six cases among them were current fluoroquinolone users, and 78 were current penicillin users. The ratio of incidence of serious arrhythmia was 0.85 when the oral treatment with fluoroquinolone and penicillin was compared. The absolute risk difference of serious arrhythmia associated with fluoroquinolone was –13 cases per 1,000,000 courses when compared with penicillin.

The result concluded that oral treatment with fluoroquinolone was associated with a lower risk of arrhythmia compared with penicillin.

Ref: https://www.bmj.com/content/352/bmj.i843