Are fluoroquinolones linked to an increased risk of aortic or mitral regurgitation? This possible association has been examined in a recently published pharmacoepidemiological study. Data from the FDA adverse reporting system database was used to analysed for a a disproportionality analysis, and a random sample of 9,053,240 patients from the U.S. PharMetrics Plus database (IQVIA) was used for the matched nested case-control study. Current fluoroquinolone exposure was classed as an active prescription at the index date or 30 days prior to the event date, recent exposure was use within days 31 to 60 and “past use” was in the range spanning days 61 to 365 prior to the event date. Rate ratios (RRs) were compared to users of amoxicillin and azithromycin. The adjusted RRs for current users of FQ compared with amoxicillin and azithromycin users were 2.40 (95% CI: 1.82 to 3.16) and 1.75 (95% CI: 1.34 to 2.29), respectively. The adjusted RRs for recent and past FQ users when compared with amoxicillin were 1.47 (95% CI: 1.03 to 2.09) and 1.06 (95% CI: 0.91 to 1.21), respectively. The risk of aortic and mitral regurgitation was found to be highest with current fluoroquinolone use, but no elevated risk was associated with past use of FQs. Read details of the study here.