Review Question - QID 212881

This patient who experienced vomiting, vertigo, headache, and weakness after ingesting alcohol most likely experienced the disulfiram-like effect of sulfonylurea drugs, which function by closing potassium channels.

Sulfonylureas are a class of diabetes drug that increase insulin release by closing potassium channels in pancreatic beta cells. These channels are normally responsive to the level of intracellular ATP and therefore close when glucose is absorbed and metabolized into ATP. Closure of these potassium channels leads to depolarization of the cell, calcium influx, and subsequent insulin release. Sulfonylureas will therefore increase the amount of insulin released in patients with type 2 diabetes. An important side effect of sulfonylureas is a disulfiram-like response to alcohol that leads to flushing, copious vomiting, headache, and weakness.

Incorrect Answers:
Answer 1: Binding to peroxisome proliferator-activating receptors is consistent with the action of thiazolidinediones; however, the major toxicity for this drug is hepatotoxicity and cardiovascular toxicity.

Answer 3: Decreasing hepatic gluconeogenesis is consistent with the action of metformin; however, the major toxicity for this drug is lactic acidosis.

Answer 4: Inhibiting alpha-glucosidase is consistent with the action of acarbose; however, the major toxicity for this drug is gastrointestinal upset.

Answer 5: Inhibiting dipeptidyl peptidase is consistent with the action of the gliptins; however, the major toxicity for this drug is pancreatitis.

Bullet Summary:
Sulfonylureas increase insulin release by closing pancreatic beta cell potassium channels.