Not positive but my doctor said it could be from caffeine withdrawl.... I used to take Excedrin all the time when I would get a headache and it'd go away, then come back as a migraine. He said I could be getting migraines when the caffeine from the pills wear off....so I should try to not have any caffeine for a while and see if it helps. I've been drinking juice, kool-aid and taking Aleve (no caffeine)...no migraines so far!

He also gave me Imitrex..he said take 3 aleve and it's equal to prescription strength naproxen and wait 2 hrs, if you still have the headache, take 1 imitrex, 2 hrs later if its still there, take another. I took allll of those pills and didnt get rid of my migraine til I slept