144034-80-0

Ca channel blocker

Rizatriptan is reported to be a very effective acute migraine drug. It is reported to display high agonist activity at mainly the serotonin 5-HT1B and 5-HT1D receptor subtypes.

ChEBI: Rizatriptan is a member of tryptamines. It has a role as a serotonergic agonist, a vasoconstrictor agent and an anti-inflammatory drug. It is functionally related to a N,N-dimethyltryptamine.

Maxalt (Merck).

Rizatriptan, approved in 1998, is a fast-acting triptan becauseof its moderate lipophilicity yet has a very shortelimination half-life similar to sumatriptan (i.e., like sumatriptan,it is mainly metabolized by MAO-A). The only advantagesof this drug when compared with sumatriptan arethat it has a slightly faster onset and that it has an orallydisintegrating tablet formulation which can be taken withoutwater.

5HT1 receptor agonist:
Acute treatment of migraine

Potentially hazardous interactions with other drugs
Antidepressants: increased risk of CNS excitation with citalopram - avoid; risk of CNS toxicity with MAOIs, moclobemide and linezolid - avoid for 2 weeks after discontinuation of MAOI and moclobemide; possibly increased serotonergic effects with duloxetine and venlafaxine; increased serotonergic effects with St John’s wort - avoid.
Dapoxetine: possible increased risk of serotonergic effects - avoid for 2 weeks after stopping 5HT1 agonists.
Ergot alkaloids: increased risk of vasospasm - avoid.
Propranolol: rizatriptan levels increased, reduce dose of rizatriptan to 5 mg (max 10 mg in 24 hours).

The main route of rizatriptan metabolism is via oxidative deamination by monoamine oxidase-A (MAO-A) to the indole acetic acid metabolite, which is not pharmacologically active. N-monodesmethyl-rizatriptan, a metabolite with activity similar to that of parent compound, is formed to a minor degree, but does not contribute significantly to the pharmacodynamic activity of rizatriptan.
Less than 1% is excreted in the urine as active N-monodesmethyl metabolite.