I'm 22 years old 6'5" and 155 lbs. I'm really skinny obviously but I take 15mg of adderall xr daily and I have no appetite at all after I take it. I have tried to force myself to eat but I just can't do it. I have an insanely fast metabolism as it is so I already had trouble keeping on weight. Never been able to go above 155 though no matter how much I ate. I have talked to my doctor about my weight and he just says keep eating all the time. He doesn't understand it's just not that easy. I was thinking about talking to him about periactin to help at least maintain my weight while on adderall. Is this a good idea? Any advice would be greatly appreciated!