A migraine is a neurological condition that causes intense, often throbbing head pain lasting anywhere from 4 to 72 hours. It affects roughly 15% of the global population, with women experiencing it three to four times more often than men (about 21% of women versus 10% of men). Unlike a regular headache, a migraine involves changes in brain activity that can produce nausea, extreme sensitivity to light and sound, and sometimes visual disturbances called aura.
What Happens in Your Brain During a Migraine
A migraine isn’t just a bad headache. It starts with a wave of electrical activity that spreads across the surface of the brain, called cortical spreading depression. This wave activates a network of pain-sensing nerves centered around the trigeminal nerve, which runs through your face and skull. Once triggered, these nerves release a signaling molecule that dilates blood vessels in the membranes surrounding the brain and promotes inflammation in the area.
This creates a feedback loop: the inflammation causes nearby cells to release even more of the same signaling molecule, which dilates more blood vessels, which triggers more inflammation. That cycle is a major reason migraines can last so long and feel so overwhelming. It also explains why migraines tend to get worse with physical movement, since anything that increases blood flow to the head intensifies the process.
The Four Phases of a Migraine
Most people think of a migraine as the headache itself, but it actually unfolds in up to four distinct stages. Not everyone experiences all four, but recognizing the early phases can help you respond sooner.
Prodrome
One to two days before the headache hits, you may notice subtle warning signs: unusual food cravings, mood swings, neck stiffness, increased thirst, frequent yawning, or constipation. These are easy to dismiss as unrelated, but they’re often the first signal that a migraine is building.
Aura
About 25% of people with migraines experience aura, a set of neurological symptoms that typically builds over several minutes and lasts 20 minutes to an hour. Visual aura is the most common type. It often starts as a small blind spot or bright, shimmering lines that expand across one side of your visual field. Some people see flashing lights, zigzag patterns, or geometric shapes.
Sensory auras produce tingling or numbness, usually in one hand or arm, sometimes spreading to one side of the face or even half the tongue. Less commonly, aura affects speech, causing temporary difficulty finding words, or produces brief weakness on one side of the body. These symptoms can be alarming, but they’re temporary and resolve as the headache phase begins.
Attack
The headache phase is what most people recognize as “the migraine.” Pain is usually on one side of the head (though it can be on both) and has a pulsing or throbbing quality. Sensitivity to light, sound, and sometimes smell and touch become intense enough that many people need to lie in a dark, quiet room. Nausea and vomiting are common. Without treatment, this phase lasts 4 to 72 hours.
Postdrome
After the headache fades, many people feel drained, foggy, or confused for up to a day. Some describe it as a “migraine hangover.” A few people feel briefly euphoric. Sudden head movements can bring back a flash of pain during this phase, even though the attack itself is over.
Common Triggers
Migraine triggers vary from person to person, but research using large tracking datasets has identified several consistent patterns. The most commonly reported nonfood triggers are disrupted sleep, stress or anxiety, storms or rain, and bright light. Among foods, caffeinated drinks (coffee and tea) top the list, followed by chocolate, wine, and cheese. These foods share a common thread: they’re all high in tannins, a plant compound that may influence brain signaling in people who are susceptible.
Interestingly, many foods people worry about, like meat, fruit, nuts, beer, and foods with additives, show up as low-risk triggers in tracking data. That doesn’t mean they can never trigger a migraine, but they do so far less frequently than the items above. Keeping a personal trigger diary remains one of the most practical ways to identify your specific patterns.
Episodic vs. Chronic Migraine
Most people with migraines have the episodic form, meaning attacks come and go with stretches of headache-free days in between. Chronic migraine is defined by the International Headache Society as having headaches on 15 or more days per month for more than three months, with at least 8 of those days meeting the criteria for migraine. The distinction matters because chronic migraine typically requires a different treatment approach, with a stronger emphasis on daily preventive therapy rather than treating individual attacks.
How Migraines Are Treated
Treatment falls into two broad categories: stopping an attack that’s already started and preventing future attacks from happening.
For stopping an active migraine, triptans have been the standard option for decades. They work by constricting dilated blood vessels and blocking pain signals in the trigeminal nerve. A newer class of medications takes a different approach by directly blocking the signaling molecule responsible for the inflammatory feedback loop described earlier. These newer options can treat an active attack and, in some cases, are also taken regularly to prevent migraines. They’re particularly useful for people who haven’t responded well to triptans or who have cardiovascular conditions that make triptans unsafe.
For prevention, people who have frequent or severe migraines may benefit from monthly or quarterly injections that neutralize the same inflammatory signaling molecule before it can start the cascade. Four such injectable treatments have been approved since 2018. Guidelines generally recommend considering these after someone has tried at least two other preventive approaches without adequate relief, and it takes about three to six months to fully evaluate whether they’re working.
Conditions Linked to Migraine
Migraine frequently coexists with other health conditions. Depression and anxiety are especially common in people with migraines, and the relationship appears to go both ways: each condition raises the risk of the other. On the cardiovascular side, migraine is now recognized as an independent risk factor for stroke, heart attack, and certain heart rhythm abnormalities. People with migraines have roughly 1.5 times the risk of hemorrhagic stroke compared to the general population.
The cardiovascular risk is particularly elevated for women under 50 who experience migraine with aura, and smoking or using oral contraceptives amplifies that risk further. This doesn’t mean a migraine will cause a stroke, but it’s useful context for understanding your overall health picture and making informed choices about other medications and lifestyle factors.