On July 8, 2008, the Food and Drug Administration (FDA) announced it notified manufacturers of fluoroquinolone drugs that a warning on the product labeling concerning an increased risk of tendinitis and tendon rupture is necessary. Manufacturers must also provide a Medication Guide to patients detailing the potential side effects.

The agency made the announcement after completing a new analysis of literature and post-marketing adverse event reports. The analysis confirmed an association between the use of fluoroquinolones and tendon rupture, and also found a continuation of large numbers of tendon-related reports.

Further, the FDA informed the manufacturers of the drugs that a Risk Evaluation and Mitigation Strategy (REMS) will need to be performed to determine if the benefits of the drugs outweigh the risks. Companies are required to submit safety labeling changes to the FDA within 30 days, or to explain why they do not believe the change is necessary.

Fluoroquinolones are approved to treat or prevent specific bacterial infections. Medications considered as fluoroquinolones are:

• Cipro, made by Bayer,
• Cipro XR, made by Bayer,
• Proquin XR, made by Depomed, Inc.,
• Factive, made by Oscient Pharmaceuticals,
• Levaquin, made by Ortho-McNeil Pharmaceuticals,
• Avelox, made by Bayer,
• Noroxin, made by Merck & Co., Inc.,
• Floxin, made by Oscient Pharmaceuticals, and
• Ofloxacin, a generic drug.

Source: “FDA requests boxed warningson fluoroquinolone antimicrobial drugs,” Food and Drug Administration Press Release, July 8, 2008.