Oral sumatriptan pharmacokinetics in the migraine state

Objective: This double-blind, parallel, multicentre study investigated the effect of migraine on absorption of oral sumatriptan (25, 50 and 100mg) com pared with placebo. Design: Patients received sumatriptan or placebo in the clinic during an ac ute migraine and at least 7 days later, when pain-free. Pharmacokinetic and efficacy (n = 192) and safety (n = 259) parameters were assessed for 4 hou rs after administration of study medication. Results: Absorption of sumatriptan from 50 and 100mg tablets was not signif icantly different between the migraine and pain-free periods. There was how ever a statistically significant decrease (approximately 23%) and delay (35 minutes) in absorption of sumatriptan from the 25mg tablet during a migrai ne compared with the pain-free period. Sumatriptan pharmacokinetics exhibit ed dose proportionality during the migraine and pain-free periods. All dose s of sumatriptan were significantly superior to placebo in reducing headach e pain. Adverse events were comparable among the sumatriptan groups and pla cebo group. Conclusions: Absorption of sumatriptan, administered at therapeutic doses, was not statistically significantly impaired during migraine versus the pai n-free state. These data suggest that coadministration of drugs that improv e the absorption of sumatriptan is not necessary during sumatriptan treatme nt.