Zolmitriptan in the acute treatment of migraine: An overview

Zolmitriptan is a 5HT(!B/1D) agonist that is indicated in the acute treatment of migraine. Preclinical studies indicate that its potential mechanisms of action include carotid vasoconstriction, inhibition of peripheral terminals of the trigeminal nerve that innervate pain-producing craniovascular structures, or inhibition of trigeminal neurons within the brainstem and upper cervical spinal cord. Clinical pharmacology studies have demonstrated that zolmitriptan has a bioavailability of 40% and is largely metabolized in the liver, partly to an active metabolite, N-desmethylzolmitriptan. Zolmitriptan 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 mild, 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 after 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 response when compared to placebo is 45 min after dosing. Zolmitriptan is an effective acute treatment for attacks of migraine.