-Data on the treatment of chronic migraine are scarce because most migraine-prevention trials excluded patients who had headaches for ≥15 days per month.
-Trial data are available for topiramate and botulinum toxin type A.
Nat Rev Neurol. 2012 Feb 14;8(3):162-71. doi:
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Chronic migraine--classification, characteristics and
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Diener HC, Dodick DW, Goadsby PJ, Lipton RB, Olesen J,
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