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.