Abstract

Fluoroquinolones are generally regarded as safe antimicrobial agents with relatively few adverse effects or drug interactions. Because of their recognized safety profile and potent in vitro activity, fluoroquinolones have been widely used for the treatment of community- and hospital-acquired infections. Although uncommon, both hypoglycaemia and hyperglycaemia (dysglycaemia) appear to occur with all the fluoroquinolones. It is usually reported in conjunction with impaired creatinine clearance and elderly diabetics receiving concomitant treatment with antidiabetic agents (especially sulfonylureas) or insulin. The exact mechanism of this effect is unknown but is postulated to be a result of blockage of adenosine 5'-triphosphate-sensitive potassium channels in pancreatic cell membranes. Here we report a case of hypoglycaemia in a hospitalized non-diabetic elderly patient in whom this life-threatening adverse effect was related in a temporal fashion to the administration of intravenous levofloxacin meant to cover pulmonary infection in a setting of subacute small bowel obstruction and septicaemia. This case emphasizes the occurrence of profound and prolonged hypoglycaemia consequent upon levofloxacin use, an adverse reaction that has been described with almost all members of the quinolone family of antibiotics. Taking into consideration the frequency of fluoroquinolones use in the hospital and ambulatory setting, clinicians should be cognizant of this potential adverse effect in non-diabetic patients treated with levofloxacin, and they should look out for symptoms of hypoglycaemia and monitor blood glucose levels more frequently, especially early in the course of therapy.