There is a lot of good information on this topic out in cancer world, so I recommend spending some time looking at cancer sites, even though you don't have cancer yourself.
Here's a good page to get you started, complete with some questions you can ask your doctor:
http://www.canceradvocacy.org/resources/treatment-issues/side-effects/appetite.htmlYou should be able to find dozens of pages with good, simple, recipes, if you just use some creative Googling.
All the best.
Ivy.