Caffeine and Adderall... what a wonderful combination.
When I'm off my Adderall, I lean more heavily on caffeine to keep my brain going at the speed I need it. This time when I got back on the Adderall, I stopped drinking sodas for a few days (the appetite suppression kinda killed my stomach for a bit and I didn't want anything but water for a while). In a way, I think caffeine withdrawal is as bad or worse for me than Adderall withdrawal (of which I get little or none, just feel somewhat sluggish and it feels like my brain "chugs").
Anyway, I take the Adderall, then I drink the caffeine, and suddenly I'm the productivity machine that I wanted to be. I found the cocktail that's right for me.