Rizatriptan

Pharmaceuticals -> Listed in ZINC15

Pharmaceuticals

178-180

178 - 180 °C

Danger

H319 (100%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]

P203, P260, P261, P264, P264+P265, P270, P271, P280, P304+P340, P305+P351+P338, P318, P319, P337+P317, P403+P233, P405, and P501 (click each P-code to see the statement)

The GHS information provided by 1 company from 1 notification to the ECHA C&L Inventory.

Gastrointestinal decontamination, (i.e., gastric lavage followed by activated charcoal) should be considered in patients suspected of an overdose with Rizatriptan. Clinical and electrocardiographic monitoring should be continued for at least 12 hours, even if clinical symptoms are not observed. (L1712)

Rapid following oral administration. Bioavailability is 45%. Food has no effect on the bioavailability of rizatriptan. However, administering rizatriptan with food will delay by 1 hour the time to reach peak plasma concentration. The rate of absorption is not affected by the presence of a migraine attack.

Three distinct pharmacological actions have been implicated in the antimigraine effect of the triptans: (1) stimulation of presynaptic 5-HT1D receptors, which serves to inhibit both dural vasodilation and inflammation; (2) direct inhibition of trigeminal nuclei cell excitability via 5-HT1B/1D receptor agonism in the brainstem and (3) vasoconstriction of meningeal, dural, cerebral or pial vessels as a result of vascular 5-HT1B receptor agonism.

N02CC04

N - Nervous system

QN - Nervous system

Rizatriptan relieves migraine-associated symptoms. Rizatriptan is reported to reach the maximum plasma concentrations more quickly and produces a more rapid onset of pain relief than other triptans, such as [sumatriptan]; however, it has a relatively shorter elimination half-life than other triptans. Rizatriptan causes transient increases in blood pressure to some extent. _In vitro_, rizatriptan was shown to contract isolated human coronary arteries; however, since the EC₅₀ for this effect is high, rizatriptan is not expected to cause myocardial ischemia at therapeutic plasma concentrations in patients with normal coronary circulation. Rizatriptan has a weak affinity for other 5-HT1 receptor subtypes (5-HT_1A, 5-HT_1E, 5-HT_1F) and the 5-HT₇ receptor but has no significant activity at 5-HT₂, 5-HT₃, alpha- and beta-adrenergic, dopaminergic, histaminergic, muscarinic or benzodiazepine receptors.

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_1B and 5-HT_1D receptors to promote trigeminal neuronal firing and vasoconstriction. Rizatriptan is a selective agonist at the 5-HT_1B and 5-HT_1D 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_1B 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_1D receptors. Rizatriptan inhibited neurogenic dural vasodilation and plasma protein extravasation in animal studies.