The Scottish Medicines Consortium (SMC) does not recommend the use of botulinum toxin type A (Botox®) within NHS Scotland for the prophylaxis of headaches in adults with chronic migraine (headaches on at least 15 days per month of which at least 8 days are with migraine).

The drug advice (available at the link below) discusses the evidence submitted by the manufacturer and considered by the SMC when making their recommendation.  This notes that botulinum toxin type A was superior to placebo for the primary endpoint of headache days in a pooled analysis of two Phase III studies; however there were weaknesses in the clinical data that limit the ability to assess its likely clinical effectiveness in the target treatment population.  Overall the manufacturer did not present a sufficiently robust clinical and economic analysis to gain acceptance by the SMC.