A 2-year prospective evaluation study on onabotulinumtoxinA 155 U in chronic migraine

To prospectively evaluate the variations in terms of headache days, migraine days, acute pain medication intake days through a period of 24 months in compari- son to a one-month baseline period before starting the therapy. Methods Among all the patients that from 2011 to 2012 under- went treatment with onabotulinumtoxinA we randomly selected 100 CM patients (F 88 / M 12; mean age 43.2, range 18-80 years; 96% drugs overusers) that were able to fill in diaries without any lack of information for a period of 2 years. OnabotulinumtoxinA 155 U was injected in 31 sites following the PREEMPT “fixed sites/fixed doses” injection paradigm every three months (± one week) [1]. Patients with criteria for medication-overuse headache underwent withdrawal and detoxification therapeutic regimen before starting the treatment. Patients were not allowed to continue preventive oral medication during treatment with onabotulinumtoxinA.