A migraine is a neurological condition that causes intense, often pulsating head pain lasting anywhere from 4 to 72 hours. It affects roughly 14% of the global population each year, making it one of the most common neurological disorders in the world. But a migraine is far more than a bad headache. It involves changes in brain activity, nerve signaling, and blood vessel function that produce a constellation of symptoms well beyond head pain, including nausea, light sensitivity, and visual disturbances.
What Happens in Your Brain During a Migraine
Migraine pain originates in a network of nerves and blood vessels surrounding the brain. The trigeminal nerve, which is the main sensory nerve of the face and head, plays a central role. During a migraine, nerve fibers surrounding the brain’s blood vessels release a signaling molecule called CGRP. This molecule triggers a chain reaction: blood vessels dilate, nearby nerve endings become hypersensitive, and inflammation builds along the surface of the brain.
What makes migraines so persistent is a feedback loop. CGRP and nitric oxide (a chemical that widens blood vessels) amplify each other’s effects throughout this nerve network. The more CGRP is released, the more nitric oxide is produced, which in turn triggers further CGRP release. This cycle sensitizes the entire pain signaling system, which is why migraines can escalate and why ordinary stimuli like light, sound, or even slight movement can become unbearable once an attack is underway.
Over the course of an attack, the pain-processing neurons in the brainstem also become sensitized. They start responding to lower-threshold stimuli and expanding their receptive range, meaning pain can spread beyond its original location. This process, called central sensitization, helps explain why migraines become harder to treat the longer they go untreated.
The Four Phases of a Migraine Attack
A migraine isn’t a single event. It unfolds in up to four distinct phases, though not everyone experiences all of them.
Prodrome begins hours to days before the headache itself. Common warning signs include neck stiffness, fatigue, sensitivity to light and sound, food cravings, and mood changes. Many people learn to recognize these signals as early indicators that a migraine is coming.
Aura occurs in about one-third of people with migraines. It typically involves visual disturbances like shimmering zigzag lines, blind spots, or flashing lights that slowly spread across your field of vision. Some people experience numbness or tingling in the face or hands, or difficulty finding words. Aura is caused by a wave of electrical activity that sweeps across the surface of the brain, temporarily disrupting normal function as it passes. It usually lasts 20 to 60 minutes and resolves before or as the headache begins.
Headache is the phase most people associate with migraine. The pain is typically moderate to severe, often on one side of the head (though about 40% of people report pain on both sides), and frequently described as throbbing or pulsating. Nausea, vomiting, and extreme sensitivity to light and sound are common. Physical activity tends to make the pain worse, which is one of the clearest distinguishing features from other headache types. This phase lasts 4 to 72 hours without treatment.
Postdrome is sometimes called the “migraine hangover.” After the headache subsides, many people feel drained, foggy, or mildly confused for hours or even a day afterward.
How Migraines Differ From Other Headaches
Tension headaches, the most common headache type, produce a dull, band-like pressure on both sides of the head. They’re mild to moderate in intensity, last 30 minutes to a day, and critically, they don’t get worse with normal physical activity like walking or climbing stairs. Migraines do. That difference alone is one of the most reliable ways to tell them apart.
Migraines also come with autonomic symptoms that tension headaches typically don’t. Eye redness and tearing occur in 30% to 75% of migraine cases. Nausea and vomiting are common with migraines but rare with tension headaches. Sensitivity to light and sound is a hallmark of migraine and is generally absent in tension-type headaches.
Common Triggers
Migraines are often set off by identifiable triggers, though they vary widely from person to person. In tracking studies using mobile apps, the most frequently reported triggers fall into a few broad categories.
Among foods and beverages, chocolate, wine, tea, coffee, and cheese top the list. Chocolate showed the strongest statistical association with migraine onset. When people consumed chocolate within 48 hours of a migraine, about 62% of those exposures were followed by an attack. Tea and coffee showed similar patterns, though the associations were less statistically robust.
Non-food triggers were equally prominent. Altered sleep patterns (too much or too little sleep) were the most commonly reported non-dietary trigger, followed closely by stress and anxiety, rain or storm conditions, and bright light. Fatigue and screen exposure also appeared frequently in self-reported data.
Hormonal fluctuations are another major factor, particularly for women. The drop in estrogen that occurs just before menstruation is one of the most well-established migraine triggers, which partly explains why women experience migraines at significantly higher rates than men.
Who Gets Migraines
About 1.16 billion people worldwide had migraines as of 2021, a 58% increase from 1990. Women are affected at substantially higher rates than men and are more likely to report migraine-related disability. However, the rate of increase in migraine cases has been four to five times faster in men than in women over the past three decades, narrowing the gap slightly.
Migraines most commonly begin in adolescence or early adulthood and tend to peak in frequency during the 30s and 40s. They often decrease in frequency after menopause in women, further supporting the role of hormonal factors.
Episodic vs. Chronic Migraine
Most people with migraines have the episodic form, meaning attacks come and go with stretches of normal days in between. Chronic migraine is defined as having headaches on 15 or more days per month, with at least 8 of those days meeting migraine criteria. This distinction matters because chronic migraine tends to be more disabling and often requires different treatment strategies.
A migraine that lasts continuously for more than 72 hours is classified as status migrainosus. This is considered a complication of migraine and can be debilitating enough to require urgent medical care. Brief remissions due to sleep or medication (up to 12 hours) don’t reset the clock.
How Migraines Are Treated
Treatment falls into two broad categories: stopping an attack that’s already started and preventing future attacks.
For stopping an active migraine, the most widely used prescription medications are triptans, a class of drugs that work by activating serotonin receptors on blood vessels and trigeminal nerve terminals. This counteracts the vessel dilation and nerve sensitization driving the attack. Seven different triptans are available, and they work best when taken early in an attack, before central sensitization sets in. Over-the-counter pain relievers like ibuprofen or acetaminophen can also help with milder attacks.
For prevention, several medication classes can reduce how often migraines occur. Blood pressure medications in the beta-blocker family have decades of evidence behind them, though exactly how they prevent migraines isn’t fully understood. Certain antidepressants and anti-seizure medications are also used preventively.
The newest class of preventive treatments targets CGRP directly, the same signaling molecule that drives the pain cascade during an attack. These medications are the only preventive treatments developed specifically for migraine rather than borrowed from other conditions. They work by either blocking CGRP itself or blocking its receptor, and they tend to produce fewer side effects than older preventive options. They’re given as monthly or quarterly injections.
Beyond medication, managing triggers plays an important role for many people. Keeping a consistent sleep schedule, managing stress, staying hydrated, and identifying personal food triggers through a headache diary can reduce attack frequency. No single approach works for everyone, and most people with frequent migraines benefit from combining lifestyle adjustments with medication.