Ergotamine

Ergotamine is an ergot alkaloid derivative. Ergotamine acts as a partial agonist at the serotonin 5-HT₁B/5-HT₁D receptors, causing constriction of intracranial blood vessels, especially dural vessels, and influencing vascular tone and neurogenic inflammatory responses in the trigeminovascular system. It also has agonist activity at the α-adrenoreceptor, leading to constriction of peripheral and intracranial blood vessels. In addition, ergotamine can inhibit the release of trigeminal neuropeptides, thereby reducing neurogenic inflammation and pain signal transmission.