I too had bad rash experiences with Wellbutrin. I was on it maybe 3 weeks when all of a sudden, I started getting hives on my stomach and neck. Also my eyelids and lips blew up and i even went to the emergency room one day when the whole left side of my face felt swollen up like a balloon.
I was shocked when my doctor didn't think it was the Wellbutrin since that was the only thing that had changed recently.
Suffice to say, without her recommendation, I stopped taking Wellbutrin and have not had those symptoms again -- and it's a full year later!