RESUMO
PURPOSE: To determine whether botulinum toxin type A (BOTOX ) is effective for the prophylactic treatment of headaches in adults. MATERIALS AND METHODS: A retrospective literature reviewwas performed. The outcome of various studies is discussed, including whether a decrease in the intensity as well as the occurrence of tension and migraine headaches was accomplished. RESULTS: The approval for botulinum toxin A for the treatment of migraine was based largely on the results of Allergan's PREEMPT Phase III trial. The study demonstrated a statistically significant decrease in the frequency of headache days and a reduction in total headache hours in the treated group vs placebo. There have been several other randomized trials looking at treatment of chronic tension type headaches with botulinum toxin A therapy. Most studies show no difference in headache intensity between groups at anytime. Current concepts of the pathophysiology of tension-type headaches would suggest Botox to be a reasonable and likely effective treatment. However, its effectiveness in treatment of chronic migraine and tension-type headaches remains debatable. CONCLUSION: The literature currently suggests a modest effect, if any, with the use of botulinum toxin A for the prophylactic treatment of chronic migraine and tension-type headache, and further prospective, randomized, double-blinded studies are needed.