 In addition to being 5-HT1B agonists, triptans (i.e.sumatriptan, almotriptan, zolmitriptan, naratriptan, eletriptan, frovatriptan and rizatriptan) are also agonists at the 5-HT1D receptor, which contributes to their antimigraine effect caused by vasoconstriction of blood vessels in the brain.The same is true for ergotamine.