Dynamic optimization of chronic migraine treatment: current and future options.

Comparator studies that assess treatment effects in a clinical setting have improved the understanding of the efficacy and tolerability of prophylactic treatments for chronic migraine (CM). It is premature to recommend device-based treatments, such as occipital nerve stimulation, vagal nerve stimulation, and patent foramen ovale closure for CM, because clinical trials are in the preliminary stages. Physical therapy techniques, like applying heat or cold packs, ultrasonography, and electrical stimulation, have been shown to lessen pain. Nonpharmacologic treatments, including cognitive behavioral therapy, stress management, and biofeedback, have been investigated and proved effective in some areas of pain management, including migraine. However, pharmacologic interventions may be necessary for effective, long-term prophylaxis. Several medications under investigation, including topiramate, gabapentin, tizanidine, and amitriptyline, have proved efficacious in reducing the number of migraine episodes and the pain associated with migraine, although adverse events may prevent continued use of some agents. Evidence supports the use of botulinum toxin type A (BoNT-A) for CM, with or without medication overuse, to achieve a significant reduction in headache episodes. Efficacy of BoNT-A for CM is comparable with or better than that of valproate and topiramate, with better tolerability. Predictors of response to BoNT-A for CM appear to include predominantly unilateral location of the headache and the presence of cutaneous or muscle allodynia. BoNT-A has been demonstrated to be safe and well tolerated, with rare discontinuations due to adverse events. Recent clinical trials indicate that rational combination therapy may have a place in treating refractory CM. Well-controlled multicenter trials are awaited.