What is the risk of tendon rupture on ciprofloxacin (fluoroquinolone antibiotic)?

Risk of Tendon Rupture with Ciprofloxacin

The risk of tendon rupture on ciprofloxacin is low but clinically significant, with approximately 12 additional cases of Achilles tendon rupture per 100,000 persons within 90 days of treatment, though this risk increases dramatically to 1 in 1,638 patients in those over 60 years of age, and escalates further to 1 in 979 patients when combined with corticosteroids. 1, 2

Baseline Risk Quantification

The absolute risk of tendon rupture with ciprofloxacin monotherapy is relatively modest but measurable:

• Any tendon rupture: 3.73 additional cases per 10,000 person-years 3
• Achilles tendon rupture specifically: 2.91 additional cases per 10,000 person-years, or approximately 12 cases per 100,000 persons within 90 days 1, 3
• Relative risk: 3.1 times higher than the general population for Achilles tendon rupture 1
• The FDA confirms fluoroquinolones are associated with increased risk of tendinitis and tendon rupture in all ages 4

High-Risk Populations with Dramatically Elevated Risk

Age Over 60 Years

• Risk increases 4-fold compared to the general population 1, 2
• Approximately 1 in 1,638 patients over 60 will experience Achilles tendon rupture when treated with fluoroquinolones 1, 2
• The FDA specifically warns that geriatric patients are at increased risk for severe tendon disorders 4

Concomitant Corticosteroid Use

• The combination of ciprofloxacin and corticosteroids increases risk with an odds ratio of 43.2 for Achilles tendon rupture 1, 2
• Approximately 1 in 979 patients will experience Achilles tendon rupture with this combination 1
• Excess risk of any tendon rupture: 21.2 cases per 10,000 person-years with combined therapy versus corticosteroids alone 3
• The FDA emphasizes this risk is "further increased" in patients on corticosteroid drugs 4

Additional Risk Factors

• Osteoarthritis: Specifically listed as a risk factor in clinical guidelines 1
• Strenuous physical activity or sports: 50% of tendon disorders occur during sports participation 2
• Previous tendon disorders (including rheumatoid arthritis) 4
• Renal failure 4
• Organ transplant recipients (kidney, heart, or lung) 4

Timing and Clinical Presentation

Onset of symptoms:

• Median: 6 days after exposure 1, 2
• Range: As early as 2 hours to as late as 6 months after discontinuation 1, 2
• Highest risk period: First 30 days following exposure 2
• Risk persists for 60 days after treatment 5

Affected tendons:

• Achilles tendon: 90% of cases, with bilateral involvement in more than half 1, 2
• Other sites: Rotator cuff, patellar tendon, biceps, hand and foot tendons 1, 4

Risk Mitigation Strategies

When ciprofloxacin must be used in high-risk patients:

• Consider magnesium supplementation during treatment if no contraindications exist, as recommended by the American College of Physical Medicine and Rehabilitation 6
• Advise complete rest at first sign of tendon pain, swelling, or inflammation 4
• Avoid unnecessary physical activity, particularly sports participation 2
• Discontinue immediately if tendon symptoms develop and switch to a non-quinolone antibiotic 4

Critical Pitfalls to Avoid

• Do not prescribe physiotherapy or NSAIDs if tendon symptoms develop—this can worsen the condition and lead to complete rupture 7
• Do not assume only the Achilles tendon is at risk—examine all major tendon sites 1, 4
• Do not ignore symptoms in younger patients—while risk is highest over 60, rupture occurs in all ages 4
• Do not overlook bilateral involvement—assess both sides even if symptoms are unilateral 2

Alternative Antibiotic Consideration

For high-risk individuals (over 60 years, history of tendon disorders, athletes, those on corticosteroids), the American College of Physicians recommends considering alternative antibiotic classes when clinically appropriate 6