An 80-year-old woman with chronic kidney disease on glibenclamide is brought to the emergency department with profound hypoglycemia requiring repeated dextrose infusions over 36 hours. The most likely explanation is:

• A Renal accumulation of active hydroxy metabolites of glibenclamide ✓
• B Hepatic conversion of glibenclamide to an active metabolite with enhanced potency
• C Autoimmune hypoglycemia triggered by sulfonylurea antibodies
• D Glibenclamide-induced inhibition of renal gluconeogenesis

Explanation

Glibenclamide is metabolized to active hydroxylated metabolites that are excreted by the kidney. In renal failure and old age these accumulate, producing severe, recurrent, and prolonged hypoglycemia that may need days of dextrose support. This is why short-acting agents such as glipizide or repaglinide are preferred in elderly patients with renal impairment. Autoimmune hypoglycemia is associated with sulfhydryl-containing drugs like captopril, not glibenclamide.

Reference: Katzung Basic and Clinical Pharmacology, 15th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.