There are a few that are known to help, and also some that are approved for being prescribed for that reason.
It's really up to you and your pdoc. and what i'm about to say, has a disclaimer that, i'm no doctor lol..
But...
a rash isn't a good thing. especially when its presenting itself on the face, or neck. (also might wanna add that med/dose/reaction to your "allergy list").
From what i've been told by a pdoc i've had, Ritalin is supose to help with appetite and weight loss, and help with add/adhd. in my experience it had the opposite effect on me.
Vyvanse is also one that "curbs the appetite", and helps with add/adhd.
Those are the only two i know of, but i'm sure there's others too.