A PLACEBO-CONTROLLED CROSSOVER STUDY OF RIZATRIPTAN IN THE TREATMENT OF MULTIPLE MIGRAINE ATTACKS

Objective: To examine the safety and efficacy of rizatriptan 10 mg PO in the treatment of multiple migraine attacks. Background: Rizatriptan is a potent and rapidly absorbed 5-HT1B/1D receptor agonist. Efficacy and general safety have been examined in controlled trials treating s ingle migraine attacks. In the current placebo-controlled study, we re port constancy of safety and efficacy of rizatriptan for patients trea ting four discrete migraine attacks. Methods: Patients with moderate o r severe migraine (n = 473) were randomized to one of five sequence gr oups, in which each patient was to treat four migraine attacks. Patien ts in four groups received rizatriptan 10 mg for three of four attacks and placebo for the remaining attack. Patients in the fifth group rec eived rizatriptan 10 mg for four attacks. Headache severity, functiona l disability, and migraine symptoms were measured immediately before d osing and at 0.5, 1, 1.5, 2, 3, and 4 hours postdose. Results: After t he first attack, response rates were 77% for rizatriptan and 37% for p lacebo (p < 0.001). Similar efficacy of rizatriptan, ranging from a 75 to 80% response, was observed in each of the subsequent attacks with no evidence of tolerance to therapeutic effects. Most patients (93%) r esponded to rizatriptan 10 mg during the first or second attack. Adver se experiences were generally mild and transient, the most common bein g dizziness and somnolence. Incidence of adverse experiences per attac k decreased after the first attack. Conclusions: Rizatriptan 10 mg PO is efficacious and generally well tolerated in acute migraine. Its eff icacy is maintained throughout the treatment of multiple, discrete mig raine attacks.