An overweight 48-year-old male presents with complaints of increased thirst and frequent urination. Laboratory examination reveals a blood glucose level of 180 mg/dL. The patient's past medical history is unremarkable, except for an anaphylactic reaction that occurred one year ago when he was given trimethoprim-sulfamethoxazole for a sinus infection. Based on this information, which of the following agents should be prescribed?
Chlorpropamide Glipizide Glucagon Metformin