ROTTERDAM, THE NETHERLANDS. Quinolones are broad-spectrum antibiotics often used to treat respiratory tract or urinary tract infections. The most commonly prescribed ones are ofloxacin (Floxin), ciprofloxacin (Cipro), and norploxacin (Noroxin). A team of British and Dutch researchers now reports that quinolone therapy is significantly associated with an increased risk for rupture of the Achilles tendon, particularly among older people and people who are also being treated with corticosteroids at the same time.
Their study is based on information obtained from the General Practice Research Database in the UK during the period 1988 through to 1998. During the study period there were 1367 reported cases of Achilles tendon rupture (ATR) or about 3.5 to 5.5 per 100,000 person-years depending on age. The use of oral corticosteroids, end-stage renal failure, rheumatoid arthritis, osteoarthritis, gout, systemic lupus erythematosus, polymyalgia rheumatica, ulcerative colitis, diabetes, and Crohn's disease were all found to be significant risk factors for ATR.
The researchers also noted a significant association between quinolone use and ATR. Patients between the
ages of 60 and 79 years had a 6-fold increased risk of ATR if using quinolones than did matched controls,
and patients over 80 years of age had a 20-fold increase in risk. The risk rose with increased daily dosage
and was highest for ofloxacin (28-fold increase) and lowest for ciprofloxacin (3.6-fold increase). The risk
also increased significantly with simultaneous use of corticosteroids. The researchers conclude that,
although the overall risk of ATR is low, it does increase significantly with age (over 60 years), increasing
dose, and concomitant use of corticosteroids.