Zolmitriptan in the acute treatment of migraine: An overview

Zolmitriptan is a 5HT(!B/1D) agonist that is indicated in the acute treatme nt of migraine. Preclinical studies indicate that its potential mechanisms of action include carotid vasoconstriction, inhibition of peripheral termin als of the trigeminal nerve that innervate pain-producing craniovascular st ructures, or inhibition of trigeminal neurons within the brainstem and uppe r cervical spinal cord. Clinical pharmacology studies have demonstrated tha t zolmitriptan has a bioavailability of 40% and is largely metabolized in t he liver, partly to an active metabolite, N-desmethylzolmitriptan. Zolmitri ptan has dose-dependent efficacy across doses from 1 to 25 mg when measured by 'headache response', in which moderate or severe pain becomes nil or mi ld, as well as by the 'headache-free' endpoint. Based on a meta-analysis of the phase II/III placebo-controlled studies, zolmitriptan has, at 2 h afte r dosing, a headache response of 64% (95% CI: 59-69%) for 2.5 mg and of 66% (95% CI: 62-70%) for the 5 mg dose. The earliest onset of a significant re sponse when compared to placebo is 45 min after dosing. Zolmitriptan is an effective acute treatment for attacks of migraine.