HNO
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The use of botulinum toxin type A for chronic migraines was studied systematically in the PREEMPT trials program. Superiority to placebo treatment was established. Thus, for the first time a prophylactic drug against chronic migraines is available that is both effective and well tolerated. Botox® was licensed in England for the prophylaxis of headaches in adults with chronic migraines (headaches on at least 15 days per month of which at least 8 days are with migraines) in 2010.