Possible gatifloxacin-induced hyperglycemia

OBJECTIVE: To report a case of possible gatifloxacin-induced hyperglycemia in a nondiabetic middle-aged woman. CASE SUMMARY: A 64-year-old Indian woman with an extensive cardiovascular history was admitted for urosepsis. On admission, her blood glucose was 117 mg/dL. She was empirically started on gatifloxacin 400 mg/day; after 3 days of gatifloxacin therapy, her blood glucose was 607 mg/dL. On day 4, therapy was changed to cefazolin for sensitive Escherichia coli and her blood glucose levels began to return to normal. DISCUSSION: Although gatifloxacin has been previously reported as a potential cause of both hyper- and hypoglycemia, the exact mechanism is unknown. Several factors that may have been involved in our patient's hyperglycemia are discussed. She experienced hyperglycemic changes more rapidly than did the typical patients of previous reports. The Naranjo probability scale suggests a possible drug-related event. CONCLUSIONS: The temporal relationship between gatifloxacin administration and the patient's hyperglycemia suggests an iatrogenic cause. Based on our experience and the product labeling, clinicians should be more aware of the blood glucose-altering effects of gatifloxacin.