UMEM Educational Pearls

Category: Toxicology

Title: Sulfonylureas

Keywords: sulfonylureas,hypoglycemia (PubMed Search)

Posted: 8/19/2010 by Fermin Barrueto, MD (Updated: 10/14/2019)
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We will all get the patient presenting with low blood glucose on a regular basis. In general, barring any underlying infection, those who are insulin dependent can be corrected with IV dextrose and/or food and be discharged. Those on a sulfonylurea may experience repeated hypoglycemic episodes and require admission - perhaps even treatment with the antidote: octreotide.

Below is the duration of action and half-life of the sulfonylureas which illustrates the need for admission:

  • Chlorpropamide (Diabinase): Duration: 24-27hrs; t 1/2: 36hrs
  • Glipizide (Glucatrol): Duration 16-24hrs; t 1/2: 7hrs
  • Glipizide XL (Glucatrol XL): Duration 24hrs
  • Glyburide (Micronase others): Duration <24hrs; t 1/2 10hrs
  • Glimepride (Amaryl): Duration 16-24hrs; t1/2: 5-9hrs

Duration of action is the physiologic effect whereas the half-life is the pharmacokinetics of elimination of the drug. Often these two numbers are different for drugs. Do not let the half-life fool you into thinking it is safe to discharge a hypoglycemic patient on a sulfonylurea.