Tendon disorders attributed to fluoroquinolones: A study on 42 spontaneousreports in the period 1988 to 1998

Objective. Fluoroquinolone antibiotics have been associated with tendinitis and tendon rupture. In this paper we report on the followup of 42 spontane ous reports of fluoroquinolone-associated tendon disorders. Methods, This study is based on cases of fluoroquinolone-associated tendon disorders reported to the Netherlands Pharmacovigilance Foundation Lareb an d the Drug Safety Unit of the Inspectorate for Health Care between January 1, 1988, and January 1, 1998. By means of a mailed questionnaire, we collec ted information on the site of injury, onset of symptoms, treatment, and co urse of the tendon disorder as well as information on possible risk factors and concomitant medication. Results. Of 50 mailed questionnaires, 42 (84%) were returned. The data conc erned 32 patients (76%) with tendinitis and 10 patients (24%) with a tendon rupture. Sixteen cases (38%) were attributed to ofloxacin, 13 (31%) to cip rofloxacin, 8 (19%) to norfloxacin, and 5 (12%) to pefloxacin. There was a male predominance, and the median age of the patients was 68 years. Most of the reports concerned the Achilles tendon, and 24 patients (57%) had bilat eral tendinitis. The latency period between the start of treatment and the appearance of the first symptoms ranged from 1 to 510 days with a median of 6 days. Most patients recovered within 2 months after cessation of therapy , but 26% had not yet recovered at followup. Conclusion. These reports suggest that fluoroquinolone-associated tendon di sorders are more common in patients over 60 years of age. Ofloxacin was imp licated most frequently relative to the number of filled prescriptions in t he Netherlands.