Rizatriptan
生产企业：Merck and co inc
Rizatriptan is a triptan used to treat migraines with or without aura.
Rizatriptan is a triptan used to treat migraines with or without aura.
There are several physiological and molecular processes implicated in the pathophysiology of migraine. Vasodilation of intracranial extracerebral blood vessels, particularly those supplying the dura mater, has been associated with migraine pain. Activation of the trigeminovascular system leads to the release of vasoactive neuropeptides (such as substance P, calcitonin gene-related peptide (CGRP), and neurokinin A) from the trigeminal nerve innervating the intracranial vessels and dura mater. Vasoactive neuropeptides cause perivascular inflammation and vasodilation in the periphery. Migraine-associated nausea and vomiting are thought to arise from the activation of central and nociceptive sensory neurons that project to autonomic brain-stem nuclei and higher subcortical and cortical pain processing centres. An imbalance in serotonin (5-HT) levels has also been documented: 5-HT binds to 5-HT and 5-HT receptors to promote trigeminal neuronal firing and vasoconstriction. Rizatriptan is a selective agonist at the 5-HT and 5-HT receptors on intracranial blood vessels and sensory nerves of the trigeminal system. It binds to these receptors with high affinity. The exact mechanism of action of rizatriptan has not been fully elucidated; however, several documented pharmacological actions of rizatriptan may contribute to its antimigraine effects. Rizatriptan causes vasoconstriction of intracranial extracerebral blood vessels, which is thought to occur primarily via 5-HT receptors. Rizatriptan also inhibits nociceptive neurotransmission in trigeminal pain pathways. It attenuates the release of vasoactive neuropeptides by the trigeminal nerve, which is thought to occur via neurogenic and central 5-HT receptors. Rizatriptan inhibited neurogenic dural vasodilation and plasma protein extravasation in animal studies.
Rizatriptan is indicated for the acute treatment of diagnosed migraine with or without aura. Rizatriptan is not indicated for the prophylactic therapy of migraine nor the treatment of cluster headache. In Canada, rizatriptan is approved in adults. In the US, the oral tablet formulations are used in patients six years of age and older and the oral film formation is approved for patients 12 years of age and older weighing 40 kg or more.
