Severe Hypoglycemia From Clarithromycin-Sulfonylurea Drug Interaction
- Robert Bussing, MD and
- Amy Gende, MD
- From the Division of General Internal Medicine, Department of Medicine, Southern Illinois University School of Medicine, Springfield, Illinois
We report two cases of severe hypoglycemia occurring in elderly men with type 2 diabetes who were prescribed clarithromycin for respiratory infections. Both individuals had well-controlled diabetes and mild to moderately impaired renal function. Both individuals were prescribed clarithromycin in identical dosages and both developed severe hypoglycemia within 48 h of starting the antibiotic. Although many drugs have been reported to interact with sulfonylureas causing hypoglycemia, the interaction between clarithromycin and a sulfonylurea has not been previously reported. We discuss the suspected mechanism for this potentially severe reaction which is of concern in the treatment of elderly patients with type 2 diabetes.
Case 1
An 82-year-old white male with a 4-month history of type 2 diabetes was treated with diet and glyburide 5 mg daily. His blood glucose readings were in the low 100s (mg/dl). His comorbidities included atherosclerotic heart disease, hypertension, mild chronic renal failure with a creatinine of 1.6 mg/dl, emphysema, and bladder cancer. In a local emergency department (ED), he was diagnosed with “bronchitis” and prescribed clarithromycin, 1,000 mg daily. He became unresponsive with an Accucheck reading of 24 mg/dl, 48 h after starting clarithromycin. Administration of intravenous …
