 This is a research study examining a migraine medicine dihydroergotamine mesylate DHE-45.It will be used to treat two migraine attacks in subjects who have a history of skin sensitivity associated with their headaches.This skin sensitivity is called cutaneous allodynia pronounced q-tay-nee-us al-o-din-ee-uh.Cutaneous allodynia is a sensation of pain when a non-noxious stimulus is applied to normal skin. It has been noted in several studies that in subjects with migraine, seventy nine percent of the subjects experienced allodynia on the facial skin on the same side as the headache. It has also been shown that that once allodynia develops, other migraine medicines that would normally be very effective for migraine pain, become much less effective or ineffective. This study will compare the differences,if any, in attacks treated early with this study drug and treated later with the same study drug. It is hoped that that this trial will provide information on the use of DHE-45 in subjects who have cutaneous allodynia. Understanding more about allodynia may help us understand how the pain system works in migraine. 