Purpose. Fluoroquinolones are generally considered safe and well-tolerated. However, suspected fluoroquinolone induced hepatotoxicity has been increasingly reported, but data are lacking. Thus, the objective of this study was to assess the risk of hepatotoxicity in patients using fluoroquinolones compared to non-users.

Methods. National Veterans Affairs (VA) hospital admissions were assessed between January 1, 2002 and December 31, 2008. Our case-control study matched patients with a primary diagnosis of hepatotoxicity (cases) to those with myocardial infarction (controls) on admission date (matched up to 1:6). Conditional logistic regression was used to compute adjusted odds ratios (OR) and 95% confidence intervals (CI) of hepatotoxicity associated with fluoroquinolone exposure.

Results. Our study included 7,862 cases and 45,512 matched controls. The majority of study patients were white (63.4%), males (97.7%), with a mean age of 61 years. After adjusting for confounders, fluoroquinolone use was significantly associated with a 20% increased risk of hepatotoxicity development (OR 1.20, 95% CI 1.04-1.38) compared to non-users. A statistically significant increased risk of hepatotoxicity was associated with ciprofloxacin use individually (OR 1.29, 95% CI 1.05-1.58), but not with levofloxacin or moxifloxacin use.

Conclusion. The use of fluoroquinolones was associated with an increased risk of hepatotoxicity relative to non-users in our national VA study population.