Stop abusing your Adderall or Dexedrine, and if you cannot do this give your medication to someone else to give to you in your prescribed dose.
Cutting back and quitting for a long period of time will also help. Eat some food, take a multi-vitamin, drink water, and get some rest.
Eventually you will have to either cut back and take a break, or stop completely when you run out of pills.
I know people who are addicted to amphetamines and stimulants who do not use them anymore, and they just drink large doses of caffeine in coffee, black tea, soda/energy drinks, or yerba mate instead.