It can be very expensive. Medical weight loss refers to surgery. There are several types, like gastric bypass, lap band procedures, where they put a band around your stomach.
They do work for many people, but it's a rough road to drive. Do a lot of research online and ask lots of questions before you choose this option.
Have you tried doing it by eating less and exercising more?

I'm trying to lose weight too and it's sooo hard. My aunt is using a weight loss product and it's really working for her. I'm gonna try it and I recommend you try it too. Check their website at http://www.getgoinfo.info , my aunt got a free trial and paid only 6.95$ shipping and handling.