Topiramate for patients with refractory migraine: an observational, multicenter study in Spain

INTRODUCTION: The efficacy of current preventive migraine treatments is limited. In addition, tolerability problems are not infrequent. OBJECTIVES: To check our experience with topiramate in the treatment of patients with refractory migraine. PATIENTS AND METHODS: We offered treatment with topiramate to patients with the diagnosis of International Headache Society (IHS) migraine who had not responded to or tolerated beta-blockers, amitriptyline, flunarizine and/or valproate. This series is made up of 115 patients (88 women), between 16 and 81 years. Most of them (n=79) fulfilled the Silberstein et al. criteria for transformed migraine. The parameters analyzed were "response" (reduction in migraine frequency>50%), excellent response (>75%) and tolerability. RESULTS: After 3 months, the maintenance doses of topiramate ranged from 25 to 400 mg, though most patients took 100 mg. Twenty-four (21%) patients withdrew due to adverse events, mostly cognitive difficulties, that had already occurred with doses as low as 25-50 mg, while 26 (23%) found topiramate ineffective. The remaining 65 (56%) patients responded, 34 with excellent response. Sixteen patients (10 obese) lost weight (3-13 kg). CONCLUSIONS: Topiramate seems to be a good therapeutic option for about half of the patients with refractory migraine. In these patients response is usually excellent. Intolerance due to adverse events appears in one-fifth of the cases early and at low doses.