Onabotulinum toxin A (Botox) for chronic migraine treatment: an Italian experience.

Chronic migraine is a common and debilitating headache syndrome. Botulinum neurotoxin, a potent toxin produced by the anaerobic bacterium clostridium botulinum, used largely for treatment of disorders associated with increased muscle tone and hyperhidrosis, is used for patients suffering from chronic migraine. In this study, a group of patients suffering from chronic migraine with medication overuse was treated with onabotulinum toxin A (Botox) to verify its efficacy for chronic migraine. The results confirmed the efficacy of onabotulinum toxin A (Botox) when used at the dosage of 155 UI according to the PREEMPT protocol. Although these results are preliminary, they led to intense efforts to evaluate the analgesic properties of onabotulinum toxin A (Botox) and to assess its use in clinical practice, in particular in migraine field.