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
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.
