<p>Migraines are likely due to local cranial vasodilatation and/or to the release of sensory neuropeptides through nerve endings in the trigeminal system. The therapeutic activity of Zolmitriptan&nbsp;for the treatment of migraine headache is thought to be due to the agonist effects at the 5-HT1B/1D&nbsp;receptors on intracranial blood vessels and sensory nerves of the trigeminal system which results in cranial vessel constriction and inhibition of pro-inflammatory neuropeptide release.</p>