The Fluoroquinolone Toxicity Research Foundation

 
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Tendon Damage Research                  See downloads for: Adobe Files



Fluoroquinolones - tendinitis : update

Australia. The Adverse Drug Reactions Advisory Committee first reported tendinitis in association with fluoroquinolone antibiotics in 1997. The Committee has continued to monitor this adverse reaction, and has now received 60 reports of tendinitis, tensosynovitis and/or tendon rupture in association with these drugs. Ciprofloxacin was most frequently cited (55 reports), as well as norfloxacin (4) and enoxacin (1).

Forty-five reports described tendinitis alone, one report described tensosynovitis, and 14 reports documented tendon tear or rupture. Fifty-five of the 60 reports specified the Achilles tendon, including 20 which described bilateral Achilles tendon damage. All 14 reports of tendon rupture involved the Achilles tendon. The 58 patients ranged in age from 38 to 91 years (median: 69), with no significant difference between those with tendinitis and those with tendon rupture.

The daily doses of ciprofloxacin ranged from 500 mg to 2250 mg, with 46% of patients taking 1500 mg and 46% of patients taking 1000 mg daily. For those who developed tendon rupture, 57% were taking 1500 mg daily. Time to onset varied from within 24 hours after the drug was commenced to 3 months after starting, but the majority of cases of tendinitis occurred within the first week. Time to rupture was longer with a median time of 2-3 weeks. Known risk factors for these reactions include old age, renal dysfunction and concomitant corticosteroid therapy. In the cases reported to the ADRAC, 29 reports documented concomitant corticosteroid use, and in 21 of the other 31 reports the patients were aged 69 years or older. In the reports of tendon rupture, 12 of the 14 described either concomitant steroid use (9) or old age (9).

Prescribers are reminded to be alert for this reaction and to withdraw the fluoroquinolone immediately when symptoms of tendinitis appear in order to reduce the risk of tendon rupture.

[See also Pharmaceuticals Newsletter Nos. 7&8, July&August 1997.]