Thanks, Nancy
The best thing to do is contact your physician for instructions while trying to get get control of your horrible rebound headaches. Dihydroergotamine (D.H.E.), an injectable ergot, helps relieve rebound headache pain during the withdrawal process. I got the information off of Mayo Clinic's website. It gives a lot of info about the withdrawal process and other informative information.
I hope this helps.
http://www.mayoclinic.com/health/rebound-headaches/DS00613/DSECTION=treatments-and-drugs