Several Months Ago I Was Diagnosed With Adult ADHD And

Several months ago I was diagnosed with Adult ADHD and treated with a generic for Adderall, D-Amphetamine. I was on 20 mg which seemed to help me focus and also remedied the extreme fatigue that at times resembled narcolepsy. However, two weeks ago my doctor increased my meds because they were no longer having the same positive effect. Now taking 30 mg, I have developed a rash/hives that has spread the past two days from my back now to my head. My back and chest itch, and my face has the feeling of a minor chemical burn or wind chapped skin. Do I simply stop taking the med until I can see my doctor Monday? Or do I need to be seen ASAP? My breathing is not restricted by it at all.