Botulinum toxin type A (BOTOX) for treatment of migraine headaches: An open-label study

OBJECTIVE: The object of this clinical experience was to evaluate the corre lation between pericranial botulinum toxin type A (BOTOX, Allergan Corp, Ir vine, CA) administration and alleviation of migraine headache symptoms. STUDY DESIGN AND SETTING: A nonrandomized, open-label study was performed a t 4 different test sites. The subjects consisted of 106 patients, predomina ntly female, who either (1) initially sought BOTOX treatment for hyperfunct ional facial lines or other dystonias with concomitant headache disorders, or (2) were candidates for BOTOX treatment specifically for headaches. Head aches were classified as true migraine, possible migraine, or nonmigraine, based on baseline headache characteristics and International Headache Socie ty criteria. BOTOX was injected into the glabellar, temporal, frontal, and/ or suboccipital regions of the head and neck. Main outcome measures were de termined by severity and duration of response. The degrees of response were classified as: (1) complete (symptom elimination), (2) partial (greater th an or equal to 50% reduction in headache frequency or severity), and (3) no response (neither (1) nor (2)). Duration of response was measured in month s for the prophylactic group. RESULTS: Among 77 true migraine subjects treated prophylactically, 51% (95% confidence interval, 39% to 62%) reported complete response with a mean (S D) response duration of 4.1 (2.6) months; 38% reported partial response wit h a mean (SD) response duration of 2.7 (1.2) months. Overall improvement wa s independent of baseline headache characteristics. Seventy percent (95% co nfidence interval, 35% to 93%) of 10 true migraine patients treated acutely reported complete response with improvement 1 to 2 hours after treatment. No adverse effects were reported. CONCLUSIONS: BOTOX was found to be a safe and effective therapy for both ac ute and prophylactic treatment of migraine headaches. Further research is n eeded to explore and develop the complete potential for the neuroinhibitory effects of botulinum toxin.