Abstract
Fluoroquinolone antibiotics (FQs) are a class of broad-spectrum antimicrobial agents widely prescribed for respiratory, urinary tract, gastrointestinal, dermatologic, and systemic infections. Commonly utilized agents include ciprofloxacin, levofloxacin, and moxifloxacin. Due to their high bioavailability, excellent tissue penetration, and potent bactericidal activity, fluoroquinolones have become a mainstay in modern infectious disease management. However, while clinically effective, a growing body of scientific literature and post-marketing surveillance data has raised significant concerns regarding their safety profile. In certain individuals, fluoroquinolones have been associated with multisystem, persistent, and sometimes disabling adverse effects that extend well beyond the period of active treatment. These reactions may involve the neurological, musculoskeletal, mitochondrial, connective tissue, and autonomic nervous systems. Regulatory agencies, including the U.S. Food and Drug Administration (FDA), have issued multiple safety communications acknowledging risks such as tendon rupture, peripheral neuropathy, central nervous system effects, dysglycemia, and aortic complications. A subset of patients experiencing prolonged or severe adverse reactions frequently describe themselves as being “floxed,” a term coined within patient communities to describe fluoroquinolone-associated toxicity (FQT). Symptoms may emerge during treatment or develop weeks to months after discontinuation, and in some cases persist for years. Reported manifestations include chronic fatigue, tendon pain or rupture, neuropathy, cognitive impairment, dysautonomia, insomnia, anxiety, muscle weakness, and gastrointestinal disturbances. Increasing evidence suggests that these clinical presentations may be linked to mitochondrial dysfunction, oxidative stress, metal chelation, collagen degradation, altered gene expression, and immune dysregulation.
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