Until recently, sulfonylureas were the only type of oral medication which could be used to lower blood sugar. This class of medications includes Glucotrol, Micronase, Diabeta, Amaryl, and the older diabetic pills such as Diabinese, Tolinase, and Orinase. Diabetics have often developed resistance to the effects of these medications after being on them for several years, and then required the use of insulin. New types of diabetic medications have allowed many diabetics to either stop insulin or reduce the amount of insulin needed. Unlike insulin and sulfonylureas, treatment with most of these new medications alone cannot result in hypoglycemic reactions.
Reactions remain a risk if combined with sulfonylureas or insulin.
Metformin works by sensitizing cells to the effect of the insulin already made by the body. Metformin will also reduce the amount of sugar released by the liver at night, helping to lower fasting blood sugars. Metformin has additional benefits including weight loss and reduction of cholesterol. They should be taken with the first bite of meals. Their most common side effect is gas.