My prescription plan does not cover weight loss drugs however, if there is a weight loss drug which is also used for other conditions, they most likely will pay. Are there any?

Adderall is prescribed for ADD/ADHD. It has some weight loss benefit.
Phentermine is an older drug. I don't know of another approved use, but it is reasonably priced in generic form.
Some anti-depressants can have weight loss as a side effect. You would need to talk with your doctor about which one.
In general I would discourage you from using the pills. I've been overweight all my adult life and I have taken a variety of prescription diet pills including fen/phen so I can speak from experience. They simply don't work long-term. They will help you lose weight but you will not keep it off unless you adopt an aggressive exercise program (10 - 15 hours per week). Most overweight people simply can't sustain the dietary changes required to keep weight off.