A 48-year-old woman with type 2 diabetes mellitus on metformin and glibenclamide (glyburide) presents to the emergency department with confusion, diaphoresis, tremor, and a capillary blood glucose of 42 mg/dL. She denies recent illness or change in medication. Her husband reports she had skipped breakfast 2 hours ago. After confirming hypoglycemia with a laboratory glucose measurement, what is the most appropriate immediate next step?