It's really nice that you care so much about her. Adipex is the brand name for Phentermine with is an appetite suppressant. I am on phentermine 37.5mg right now and it does wonders on my apetite. I do get hungry, but really never feel like eating much. It is pretty safe (as long as you take it as directed and have a doctor watch you), it's been around for 40+ years and it's the only effective medication that has helped me to lose weight.
I don't think you have anything to worry about, just be supportive and i'm sure everything will be okay