Risks Associated with Fluoroquinolone Use

Musculoskeletal Complications

• Current fluoroquinolone use increases the risk of any tendon disorder, tendon rupture, and specifically Achilles tendon rupture, with an odds ratio of 1.7, 1.3, and 4.1, respectively, in the general population 1
• The absolute risk is approximately 12 additional Achilles tendon ruptures per 100,000 persons within 90 days of treatment 1
• Symptoms of tendon disorders typically occur within 1 week of exposure, with a median of 6 days, but can appear as early as 2 hours after initial dose or as late as 6 months after discontinuation 2
• Bilateral involvement occurs in more than half of cases, and while the Achilles tendon is most commonly affected, other tendons can be involved, including patellar, rotator cuff, flexor hallucis longus, supraspinatus, and hand/foot tendons 2
• Only 26% of patients fully recover from tendon disorders, with 74% reporting persistent pain and disability at follow-up 2
• Age over 60 years increases the risk of Achilles tendon rupture to 1 per 1,638 treated patients, which is 4-fold higher than the general population 1
• Concomitant corticosteroid use dramatically escalates the risk of Achilles tendon rupture to 1 per 979 patients, with an odds ratio of 43.2 1
• Athletes and physically active individuals are at higher risk, with 50% of fluoroquinolone-associated tendon disorders occurring during sports participation 1
• Underlying conditions such as osteoarthritis, rheumatoid arthritis, diabetes mellitus, end-stage renal disease/hemodialysis, gout, and hypercholesterolemia may also increase the risk of tendon disorders 1

Pediatric Considerations

• Long-term 5-year follow-up data showed cumulative musculoskeletal adverse events were slightly higher in comparator groups, suggesting an acceptable safety profile in children when clinically indicated 3
• Achilles tendon rupture remains rare in pediatric populations 3

Critical Management Pitfalls

• The American College of Physical Medicine and Rehabilitation recommends considering magnesium supplementation during fluoroquinolone treatment if no contraindications exist, since fluoroquinolones chelate magnesium affecting collagen synthesis 4