The article “Quinolones and Tendon Ruptures” by Casparian et al is part of a growing number of reports of serious side effects associated with the use of fluoroquinolones, including ciprofloxacin. The fluoroquinolones are a class of synthetic antimicrobial agents that were modeled after nalidixic acid, a nonfluorinated quinolone antibiotic with a narrow spectrum of activity that was largely limited to treating urinary tract infections.

During the 1980s, modifications of the quinolone structure were made. It was discovered that a fluorine atom on the number 6 carbon, among other small changes, greatly enhanced the spectrum of antibacterial activity. Thus, as a result of their broad spectrum activity against causative pathogens resistant to older antimicrobial agents, these new 6-fluoroquinolone antibiotics have become extremely useful in a variety of infections: urinary tract, soft tissue, respiratory, and bone and joint infections, as well as typhoid fever, sexually-transmitted diseases, prostatitis, community- acquired pneumonia, acute bronchitis, and sinusitis. These broad spectrum agents have also been shown to be highly effective in treating complicated skin and skin structure infections, which are often polymicrobial, as well as for the more severely complicated infections of the feet of diabetic patients.