Nortriptyline
"I was going to the emergency room 3 times a week.  They would give me a shot of Compazine and send me home.  I would fall asleep, but when I woke up the headache would come back. These were the worst headaches I've ever had and nothing, even Imitrex wouldn't help.  After I was on Nortriptyline for 3 days, my headaches became manageable with Excedrin.  I now rarely have headaches.  My Doctor has increased my dosage once."