For Years I Have Been Taking Adderall, Well Around December

For years I have been taking adderall, well around december 12 2015 I stopped taking it because I was on winter break and felt I didn't need it because i didn't have to do anything that required me to really focus. Soon after I stopped, I developed itchiness to my neck, chest, and ankles. It happens if I am working out, I am feeling stress out + i'm somewhere warm or if I am somewhere where it is warm. If it's warm inside a building I am more likely to become itchy, I think this is because there is less air flow inside a building than if i were to be outside. If I'm somewhere warm then the likeliness of it happening increases. I try to fight the urge to itch but 90% of the time I fail. When I itchy it only gets worse, or when it happens I become focused on it and the itchiness gets worse. When it becomes intense i become so focused on i that all I want to do is leave the situation i'm in and go somewhere where i can cool off. When the itchiness gets bad I will get a rash over my body and on my neck