Which of the following oral antidiabetic drugs is an example of biguanides?

A) rosiglitazone (Avandia)
B) metformin (Glucophage)
C) glyburide (Micronase)
D) glipizide (Glucotrol)

B) metformin (Glucophage)
The oral antidiabetic drug called metformin (Glucophage) is an example of the biguanides. These agents keep the blood sugar levels from increasing too high or too fast after meals.