What is the difference between Glipizide, Gliclazide and Metformin?

Q: What is the difference in the function of Glipizide, Gliclazide and Metformin in controlling glucose levels? In the market medicines are available in combination. Are these effective? Is there a side effect of these medicines from sex point of view like erectile dysfunction?

A:Metformin belongs to a different group than other 2 drugs. Metformin is insulin sensitiser and other 2 produce insulin from pancreas. They don't have any side effect as such, but need to be taken under care of physician. They don't affect erectile function.