Treatment of chronic migraine headache with onabotulinumtoxinA.

Chronic migraine headache remains an exceedingly difficult entity to manage. Treatment of chronic migraine headache with onabotulinumtoxinA has recently been shown to be effective in reducing the severity and frequency of chronic migraine headache, in the PREEMPT trials, a landmark achievement. However, the studies use a primarily fixed dose and site approach to treatment, allowing some individualized injections. However, the authors do not address the issue of myofascial trigger points as potential triggers of migraine that could be inactivated using onabotulinumtoxinA, despite several studies that support the role of myofascial trigger points in initiating some migraine headaches.