What is a migraine?

Migraine is far more than a bad headache: untreated attacks typically last between 4 and 72 hours and can be disabling. About a quarter to a third of people with migraine experience an aura beforehand, such as flashing lights, zigzag lines or tingling. The condition affects around one billion people worldwide and is roughly three times more common in women than in men, partly because of hormonal changes. Attacks involve the trigeminal nerve system and a molecule called CGRP, which widens blood vessels and triggers inflammation around the brain. The first drugs designed to block CGRP were approved in 2018, and the Global Burden of Disease study ranks migraine among the leading causes of disability worldwide.