Migraine is a primary headache disorder manifesting as recurring attacks, usually lasting for 4 to 72 hours and involving pain of moderate to severe intensity (IHS 2004).
Typical characteristics of the headache are unilateral location, pulsating quality, moderate or severe intensity, and aggravation by routine physical activity. Sufferers may also experience auras, photophobia, phonophobia, nausea and vomiting. Migraine is a common disorder (Olesen 2007); a UK follow-up study found the migraine incidence rate to be 3.69 cases per 1,000 person-years, and to be around 2.5 times higher in women than men (Becker 2008).
Many people with migraine can be adequately treated when the attacks occur, but some need prophylactic interventions, as their attacks are either too frequent or are insufficiently controlled in this way. Several drugs, such as beta-blockers, amitriptyline or sodium valproate, are used in the prophylaxis of migraine in an attempt to reduce attack frequency, but all these drugs are associated with adverse effects (DTB 1998).
Acupuncture can help in the treatment of migraine by:
Providing pain relief – by stimulating nerves located in muscles and other tissues, acupuncture leads to release of endorphins and other neurochumoral factors and changes the processing of pain in the brain and spinal cord (Zhao 2008, Zijlstra 2003, Pomeranz, 1987)
Reducing inflammation – by promoting release of vascular and immunomodulatory factors (Kim 2008, Kavoussi 2007, Zijlstra 2003).
Reducing the degree of cortical spreading depression (an electrical wave in the brain associated with migraine) and plasma levels of calcitonin gene-related peptide and substance P (both implicated in the pathophysiology of migraine) (Shi 2010).
Modulating extracranial and intracranial blood flow (Park 2009).
Affecting serotonin (5-hydroxytriptamine) levels in the brain (Zhong 2007). (Serotonin may be linked to the initiation of migraines; 5-HT agonists (triptans) are used against acute attacks.)