Migraine

Migraine (UK, US) is a genetically influenced complex neurological disorder characterized by episodes of moderate-to-severe headache, most often unilateral and generally associated with nausea and light and sound sensitivity. Other characterizing symptoms may include nausea, vomiting, cognitive dysfunction, allodynia, and dizziness. Exacerbation of headache symptoms during physical activity is another distinguishing feature. Up to one-third of migraine sufferers experience aura: a premonitory period of sensory disturbance widely accepted to be caused by cortical spreading depression at the onset of a migraine attack. Although primarily considered to be a headache disorder, migraine is highly heterogenous neurological disease in its clinical presentation and is better thought of as a spectrum disease rather than a distinct clinical entity. Disease burden can range from episodic discrete attacks to chronic disease. Migraine is believed to be due to a mixture of environmental and genetic factors that influence the excitation and inhibition of nerve cells in the brain. An older "vascular theory" postulated that the headache of migraine is produced by vasodilation and aura by vasoconstriction, but this mechanism has been disproven. The currently accepted theory suggests that multiple primary neuronal impairments lead to a series of intracranial and extracranial changes, triggering a physiological cascade that leads to migraine symptomatology. Initial recommended treatment is with simple pain medication such as ibuprofen and paracetamol (acetaminophen) for the headache, medication for the nausea, and the avoidance of triggers. Specific medications such as triptans or ergotamines may be used in those for whom simple pain medications are not effective. Caffeine in combination with other analgesics is safe and effective in treatment of acute migraine. Globally, approximately 15% of people are affected by migraine. In the Global Burden of Disease Study, conducted in 2010, migraines ranked as the third-most prevalent disorder in the world.