Has anyone dealt with the headaches of withdrawal from a caffeine addiction? I have a friend who attempted to end her addiction to Coca Cola, cold turkey. The reason is that she drank so much Coca Cola, usually cracking one open first thing in the morning and worked through six packs throughout the day. Especially in our region of the country, people are known for additions to drinking "coke." Eventually, the "coke" began to work its way into the lining of her stomach and caused ulcers. Her doctor basically informed her that it was like pouring down battery acid. Not to mention the wear it was causing the enamel of her teeth. And the caffeine in addition to all the sweet tea she was drinking has been a bit much. However, suddenly quitting has caused a new issue in the form of chronic headaches. So much that she can swing from sobbing spontaneous to unable to concentrate at work. Is it possible that your brain becomes so used to caffeine, it needs it to survive? How long does the headache stage last?