Within-patient consistency of response of rizatriptan for treating migraine

To determine the within-patient consistency of response for rizatriptan, a 5-HT(1B/1D) receptor agonist for the acute treatment of migraine. Post hoc analysis was performed on data from a randomized, double-blind, placebo-controlled clinical trial. Four hundred seventy-three patients with migraine diagnosed according to the criteria of the International Headache Society were randomly assigned to one of five sequence groups in which each patient was scheduled to treat four separate moderate or severe migraine attacks. Patients in four groups received 10 mg of rizatriptan for three of four attacks and placebo for the remaining attack; patients in the fifth group received 10 mg of rizatriptan for all four attacks. Headache severity, functional disability, and associated migraine symptoms were measured immediately before dosing and at regular intervals up to 4 hours after the dose. The analysis was based on efficacy at 2 hours after dosing, the last time point before escape medications were allowed. The percentages of patients who responded in a specified number of attacks after treatment with rizatriptan were calculated. The analysis was descriptive, and no formal statistical testing was performed. Of the evaluable patients who treated three migraine attacks with 10 mg of rizatriptan (with an additional interspersed placebo-treated attack in most patients), 216 of 252 (86%) had pain relief (reduction of pain to mild or none), 122 of 252 (48%) were pain free, 211 of 250 (84%) had no nausea, 163 of 251 (65%) had no photophobia, 182 of 252 (72%) had no phonophobia, 136 of 249 (55%) had no functional disability, and 233 of 252 (92%) had no need for escape medications at 2 hours after dosing in at least two of three attacks. The response to 10 mg of oral rizatriptan within individual patients was consistent over three attacks on a range of measures.