Identify the drug that does not lower blood glucose levels from the following options.

Explanation

Ethosuximide is primarily an anticonvulsant medication used to treat absence seizures and does not influence blood sugar levels. Tolbutamide and Glibenclamide belong to the sulfonylurea class, which lowers blood glucose by stimulating insulin release. Glucagon, a hormone, actually increases blood glucose, but it is not a hypoglycemic agent. Since the question asks for a drug that does not reduce blood sugar, Ethosuximide is the correct choice.