Edit: Ask your doctor about Marinol, it’ll possibly make you munch your heart out. :) (it’s legal THC, and your condition seems chronic enough to warrant the use)

Re the edit- I just use the real thing. It's illegal here in Indiana, but it's legal in neighboring Illinois and I'm very close to the state line. It helps with my trigeminal neuralgia (the nerve disorder) but it hasn't done anything about my appetite. The only thing it does in regards to this problem is help settle my stomach after the morning heaving.

If you are a heavy cannabis user, they have to use stronger anesthesia on you, but I seem to be able to tolerate anesthesia without any long-term effects, so that wasn't a concern.