A Study of Fluoroquinolones Exposure and Collagen-Related Serious Adverse Events

Participants will not receive any intervention as a part of this study. The FQ include all oral forms of FQ (24-hours extended release tablets, extended release tablets, oral solution, oral suspension, oral tablet, pack). The drugs included are ciprofloxacin, gatifloxacin, gemifloxacin, levofloxacin, moxifloxacin, norfloxacin, ofloxacin.

Participants will not receive any intervention as a part of this study. Other antibiotics include amoxicillin, azithromycin, trimethoprim and trimethroprim/sulfamethoxazole.

Febrile illness not treated with antibiotics is defined as: concurrent diagnoses of viral disease with concurrent fever, and no concurrent prescription for any antibiotic during the 60-day period before and after the first date of viral disease diagnosis; or a diagnosis of influenza with no concurrent inpatient admission during the 60-day period pre- or post-influenza diagnosis, and no prescription for any antibiotics during the 60-day period pre- or post-influenza diagnosis.