According to the DailyMed website, sumatriptan succinate causes vasoconstriction in the human basilar artery and in the vasculature of dura matter that surrounds the brain, which can abort migraine pain caused by excessive blood flow. In addition to vasoconstriction, sumatriptan may also affect the trigeminal nerve in a way that regulates other cranial blood vessels. It is important to note, however, that Imitrex will only abort a migraine headache that has already begun; it will not prevent migraine headaches or reduce the number of attacks.
The DailyMed website notes that three clinical studies demonstrated the effectiveness of sumatriptan in reducing headache pain beyond that of placebo. On average, sumatriptan was able to reduce a moderate or severe migraine headache to a mild headache or none at all in 75 percent of patients. It was also noted that the 100 mg tablets were no more effective than the 50 mg tablets. Imitrex without prescription
Imitex is available without prescription in the United Kingdome. What you need to know about Imitrex