26.01 Migraine

Migraine affects 10-15% of the population, being more common in females, and with peak prevalence between 35 and 45 years of age. Migraine symptoms comprise a unilateral (sometimes contralateral), localized, throbbing headache that may persist for 72 hours, often accompanied by nausea and vomiting, photophobia (light sensitivity) and phonophobia (sound sensitivity). Roughly 20% of sufferers experience an “aura” preceding the headache. The aura may involve visual disturbances such as scintillating zig-zag lines, scotoma (blind spot), or blurred vision, accompanied by transient aphasia, chills, vertigo, or unilateral parasthesia (numbness or weakness).

The actual cause of migraine is unknown, and it can be triggered by almost anything, but most commonly psychosocial, environmental, neurochemical and neuroendocrine changes. Known triggers in susceptible individuals include cheese, chocolate, alcohol, chemicals, sunlight, hormones, and the contraceptive pill.