A migraine is a neurological condition that causes intense, throbbing head pain, usually on one side of the head, often accompanied by nausea, sensitivity to light or sound, or vision changes

A migraine is not simply a bad headache. It is a medical condition involving your nervous system that produces a specific pattern of symptoms. The pain typically throbs or pulses, builds over minutes to hours, and can last anywhere from 4 to 72 hours. Many people describe it as debilitating—the kind of pain that makes it hard to work, think, or be around others.

What makes a migraine different from other headaches is that it often comes with other symptoms beyond head pain. These can include nausea or vomiting, extreme sensitivity to light (photophobia), sensitivity to sound (phonophobia), or sensitivity to smell. Some people see visual disturbances before the migraine pain starts, such as flashing lights, zigzag lines, or temporary blind spots. These warning signs are called an aura.

Migraines affect roughly one in seven people at some point in their lives. They are more common in women than men, and they often run in families. A migraine is a real medical condition with measurable changes in brain activity and blood flow, not something that is "all in your head" in the sense of being imaginary.

Key Takeaways

  • A migraine causes throbbing pain, usually on one side of the head, and often includes nausea, light sensitivity, or vision changes that last 4 to 72 hours.
  • Some people experience an aura—visual disturbances like flashing lights or blind spots—minutes to hours before migraine pain begins.
  • Migraines involve changes in brain activity and blood vessel function, which is why they feel and behave differently from tension headaches.
  • Triggers vary widely between people but commonly include stress, hormonal changes, certain foods, sleep disruption, and environmental factors.
  • A doctor can diagnose a migraine based on your description of symptoms and the pattern of your headaches, without needing special imaging in most cases.

How a migraine develops: the four phases

Doctors recognize that migraines often unfold in stages, though not everyone experiences all of them. Understanding these phases can help you recognize when a migraine is starting and take action early.

Prodrome is the earliest phase, occurring hours or even a day before pain begins. You might notice mood changes, food cravings, fatigue, or difficulty concentrating. Many people do not realize this is part of the migraine until they look back after the pain starts.

Aura is the second phase and happens in roughly one-third of people with migraines. It involves temporary neurological symptoms that develop over 5 to 60 minutes. Most commonly, people see visual changes: flashing lights, zigzag lines, or a blind spot that grows across the visual field. Some people experience tingling in the face or hands, difficulty speaking, or weakness on one side of the body. The aura always goes away, and the migraine pain may or may not follow.

Attack is the pain phase itself. The headache typically starts on one side of the head and throbs or pulses. It builds in intensity and is often accompanied by nausea, vomiting, and sensitivity to light, sound, or smell. During this phase, most people want to lie down in a dark, quiet room. The pain can last 4 to 72 hours.

Postdrome is the recovery phase after the pain ends. You might feel exhausted, foggy, or emotionally drained for hours or even a day afterward. Some people feel unusually energized instead. This phase is real and is part of the migraine cycle.

What triggers a migraine

Migraine triggers are highly individual—what sets off one person's migraine may have no effect on another. However, certain factors appear frequently across many people. Stress and stress relief (the "letdown" after a stressful period) are common triggers. Hormonal changes related to the menstrual cycle trigger migraines in many women. Sleep disruption—either too little or too much—can bring one on.

Certain foods and drinks are reported triggers by some people, including aged cheeses, cured meats, chocolate, caffeine, and alcohol (especially red wine and beer). Skipping meals or fasting can also trigger migraines. Environmental factors such as bright lights, strong smells, loud noise, or changes in weather or barometric pressure affect some people.

Physical exertion, dehydration, and overuse of pain-relief medication can all play a role. The key is that triggers are personal. Keeping a migraine diary—noting when migraines occur, what you were doing, what you ate, and your stress level—can help you and your doctor identify your specific patterns.

How doctors identify a migraine

Your doctor will diagnose a migraine primarily by listening to your description of your headaches and asking detailed questions about the pattern, location, and accompanying symptoms. There is no blood test or imaging scan that definitively proves you have migraines. Instead, doctors use a set of criteria based on the characteristics of your pain and symptoms.

For a diagnosis of migraine without aura, doctors typically look for at least five headaches that meet these criteria: pain on one side of the head, throbbing quality, moderate to severe intensity, lasting 4 to 72 hours, and accompanied by nausea or vomiting, or sensitivity to light and sound. For migraine with aura, the pattern is similar, but the aura symptoms must occur before or during the headache.

Your doctor may order imaging such as an MRI or CT scan if your headaches are new, have changed in pattern, or are accompanied by neurological symptoms that do not fit the typical migraine picture. In most cases of long-standing migraines with a consistent pattern, imaging is not necessary.

The difference between migraine and other types of headaches

A tension headache is the most common type of headache and feels very different from a migraine. Tension headaches produce a pressing or squeezing sensation, usually on both sides of the head, and rarely involve nausea or sensitivity to light. They typically last 30 minutes to a few hours and do not worsen with physical activity. You can usually function during a tension headache, even if you are uncomfortable.

A cluster headache is rare but severe. It causes intense pain around one eye, occurs in clusters of multiple headaches over weeks or months, and is followed by long headache-free periods. Cluster headaches are much shorter than migraines (15 to 180 minutes) and do not usually involve nausea or aura.

A sinus headache is caused by inflammation or infection in the sinuses and produces pressure or pain in the face, forehead, or between the eyes. It often comes with nasal congestion or discharge. True sinus headaches are less common than people think; many headaches blamed on sinus problems are actually migraines.

Why migraines happen in the brain

The exact cause of migraines is still not fully understood, but researchers have identified several key processes. Migraines involve changes in brain chemistry, particularly involving a chemical messenger called serotonin. During a migraine, serotonin levels fluctuate, which affects blood vessels and nerve activity in the brain.

The trigeminal nerve, a major nerve in the face and head, plays a central role. When this nerve becomes activated, it releases substances that cause inflammation around blood vessels and nerves in the brain. This inflammation, combined with changes in blood flow, produces the throbbing pain and other symptoms you feel.

Genetic factors matter too. If both your parents have migraines, your risk is higher. If one parent has migraines, your risk is still elevated. This does not mean you will definitely have migraines, but it does mean your brain may be wired in a way that makes migraines more likely when triggered.

When to see a doctor about headaches

You should see a doctor if you have frequent headaches that follow a pattern, if headaches are interfering with your work or daily life, or if you are taking pain medication more than two days per week. You should also see a doctor if your headaches have changed—if they have become more frequent, more severe, or different in character than they used to be.

Seek immediate medical attention if a headache is accompanied by fever, stiff neck, confusion, vision loss, difficulty speaking, weakness, or numbness. These can be signs of a more serious condition. Also seek urgent care if you have the worst headache of your life, or if a headache follows a head injury.

If you have been diagnosed with migraines and your current treatment is not working well, or if your migraine pattern has changed, contact your doctor. There are many treatment options available, and what works best may change over time.

Frequently Asked Questions

Can a migraine cause permanent brain damage?

No. While migraines involve changes in brain activity and blood flow, they do not cause permanent structural damage to the brain. However, very frequent migraines may slightly increase the risk of stroke in some people, which is one reason why managing migraines well is important. Your doctor can discuss your individual risk.

Why do migraines run in families?

Migraines have a genetic component, meaning the tendency to have migraines can be inherited. If your parents or close relatives have migraines, your brain may be more sensitive to the triggers that set off migraine activity. This does not mean you will definitely have migraines, only that your risk is higher.

Is a migraine the same as a stroke?

No. A migraine is a neurological condition involving temporary changes in brain activity. A stroke occurs when blood flow to part of the brain is blocked, causing permanent damage. However, some migraine symptoms (like weakness or vision loss from an aura) can resemble stroke symptoms, which is why it is important to see a doctor if your symptoms are new or different.

Can stress cause a migraine?

Yes. Stress is one of the most commonly reported migraine triggers. Interestingly, migraines often occur during the relaxation period after stress ends, not during the stressful event itself. This is sometimes called a "letdown migraine" and is why some people get migraines on weekends or vacations.

Do all migraines involve an aura?

No. About two-thirds of people with migraines never experience an aura. Migraine without aura is actually more common than migraine with aura. Both types involve the same throbbing head pain and accompanying symptoms; the difference is whether visual or other neurological symptoms occur beforehand.