A migraine is a neurological condition that causes intense, often pulsating head pain lasting anywhere from 4 to 72 hours. It’s far more than a bad headache. Migraine attacks involve changes in brain activity that trigger pain signaling, nausea, and extreme sensitivity to light and sound. Nearly one in three people worldwide experiences a headache disorder, and migraine is among the most disabling, ranking sixth globally for health loss.
How a Migraine Differs From a Regular Headache
A tension headache typically produces a dull, pressing sensation on both sides of the head. A migraine is a different experience entirely. The pain is usually on one side, has a throbbing or pulsating quality, and ranges from moderate to severe. Routine physical activity like walking or climbing stairs makes it worse, which is why most people retreat to a dark, quiet room during an attack.
Migraine also comes with a package of other symptoms that ordinary headaches don’t. Nausea is common, sometimes with vomiting. Light becomes painful (photophobia), and normal sounds feel overwhelming (phonophobia). Some people notice their scalp is tender to the touch or that smells they’d normally ignore become intolerable. These features together are what distinguish migraine from other types of headache.
The Four Phases of a Migraine Attack
A migraine isn’t just the headache itself. Most attacks move through distinct phases, though not everyone experiences all of them.
Prodrome
Hours to days before the pain starts, subtle warning signs can appear: neck stiffness, fatigue, light and sound sensitivity, food cravings, mood changes, or difficulty concentrating. Many people learn to recognize these signals over time, which can provide a window to take medication early.
Aura
About one-quarter to one-third of people with migraine experience aura, a set of sensory disturbances that typically develop within the hour before the headache. Visual aura is the most common type. You might see zigzag lines floating across your field of vision, shimmering spots or stars, or blind spots outlined by simple shapes like circles. Less commonly, aura involves tingling in the face or hands, difficulty speaking, or a sense of numbness that spreads slowly. Aura symptoms generally last less than 60 minutes and then fade as the headache begins.
Headache
This is the main event: the throbbing, one-sided pain that can last 4 to 72 hours if untreated. In children and adolescents, attacks can be shorter, sometimes lasting as little as two hours. The pain builds gradually and is often accompanied by nausea, vomiting, and heightened sensitivity to light, sound, and smell. If you fall asleep during an attack and wake up pain-free, the duration counts until waking.
Postdrome
Even after the pain resolves, many people feel what’s sometimes called a “migraine hangover.” This recovery phase can last a few hours to two full days and includes fatigue, body aches, difficulty concentrating, dizziness, and lingering sensitivity to light and sound. Some people describe feeling foggy or mentally drained. Mood changes are common too, ranging from mild depression to, surprisingly, euphoria.
What Happens in the Brain During a Migraine
Migraine was once thought to be purely a blood vessel problem. The current understanding is more complex: it starts with abnormal brain activity that sets off a chain reaction involving the nervous system and blood vessels together.
Something triggers the brain’s pain-signaling network, often beginning with changes in a region called the hypothalamus or with increased electrical excitability in the brain’s outer layer. This activation travels along the trigeminal nerve, the main sensory nerve of the face and head. When those nerve fibers become excited, they release a signaling molecule called CGRP from their endings near the blood vessels surrounding the brain.
CGRP is a powerful vasodilator, meaning it widens blood vessels, but its role in migraine goes beyond that. Once released, it triggers a cascade: blood vessels dilate, nearby nerve endings become sensitized, and inflammatory signals ramp up around the brain’s protective membranes. This sensitization makes the nerve fibers increasingly reactive to stimulation, which is why even your own pulse pounding through blood vessels can register as throbbing pain. CGRP also signals back into the nerve cluster it came from, interacting with neighboring nerve cells and support cells to keep the sensitization going in a self-reinforcing loop.
In people who experience aura, a wave of electrical activity sweeps slowly across the brain’s surface before the headache begins. This wave releases potassium, hydrogen ions, and inflammatory substances that can activate those same trigeminal nerve endings, linking the aura directly to the pain that follows.
Common Migraine Triggers
Triggers vary widely from person to person, but certain patterns come up consistently. Stress is the most frequently reported trigger, both during high-stress periods and, paradoxically, during the “letdown” after stress passes (like a weekend after a hard workweek). Hormonal shifts explain why migraine is roughly two to three times more common in women than men, with attacks often clustering around menstruation.
Sleep disruption in either direction, too little or too much, is a reliable trigger for many people. Skipping meals, dehydration, and alcohol (especially red wine) are also well-established. Certain foods can play a role in susceptible individuals. Aged cheeses, cured meats, and fermented foods contain compounds like tyramine and histamine that may provoke attacks. Histamine in particular can act on the central nervous system and worsen migraine in people whose bodies are slower to break it down. Weather changes, bright or flickering lights, and strong smells round out the common list.
Keeping a headache diary for a few months is one of the most practical things you can do. Patterns that aren’t obvious in the moment often become clear when you track them over time.
Episodic Versus Chronic Migraine
If you have migraine attacks but fewer than 15 headache days per month, that’s classified as episodic migraine. Chronic migraine means you experience headaches on 15 or more days per month, with at least 8 of those days having migraine features, for three months or longer. Roughly 1% of the global population has chronic migraine, and it’s significantly more disabling than the episodic form.
Chronic migraine often develops gradually from episodic migraine over months or years. Overuse of acute pain medications is one of the most common factors that drives this progression. Using pain relievers (including over-the-counter options) on more than 10 to 15 days per month can paradoxically make headaches more frequent, a condition called medication-overuse headache.
How Migraine Is Treated
Migraine treatment falls into two categories: stopping an attack once it starts (acute treatment) and reducing how often attacks happen (preventive treatment).
For acute treatment, the key is timing. Taking medication early in the attack, ideally during the prodrome or when pain is still mild, is far more effective than waiting until the pain peaks. Over-the-counter pain relievers work for mild to moderate attacks in many people. For more severe migraine, a class of prescription medications called triptans has been a mainstay for decades. These work by narrowing blood vessels and blocking pain pathways in the brain.
Preventive treatment becomes important when attacks are frequent (generally four or more per month), severely disabling, or not responding well to acute medications. Traditional preventive options include certain blood pressure medications, antidepressants, and anti-seizure drugs that were found to reduce migraine frequency as a side benefit. These work for many people but weren’t designed specifically for migraine.
The newer generation of preventive treatments targets CGRP directly, the molecule at the center of migraine’s pain cascade. Four injectable antibodies have been approved that either block CGRP itself or its receptor, reducing attack frequency for many patients who didn’t respond to older options. A newer class of oral medications called gepants also blocks the CGRP receptor and can be used for both acute treatment and prevention. These represent the first treatments designed from the ground up based on migraine biology rather than borrowed from other conditions.
When a Migraine Becomes Dangerous
Most migraine attacks, while miserable, resolve on their own or with treatment. A migraine that lasts longer than 72 hours is classified as status migrainosus. The symptoms are the same as a typical migraine (throbbing one-sided pain, nausea, light sensitivity) but more intense and unrelenting. Prolonged vomiting can lead to dehydration, and the sustained pain itself becomes a medical concern. Status migrainosus drives many emergency department visits each year, particularly when vomiting prevents someone from keeping down fluids or oral medications.
Any headache that comes on suddenly and severely (“thunderclap” onset), is accompanied by fever and stiff neck, follows a head injury, or involves weakness, confusion, or trouble speaking warrants immediate medical attention. These aren’t typical migraine patterns and can signal something more serious.