What is migraine?

Migraine is more than a bad headache. It is a common neurological disease that causes attacks of head pain lasting 4 to 72 hours. The pain is often throbbing and usually comes with nausea or sensitivity to light and sound. Because no one can see it between attacks, migraine is often brushed off as “just a headache.” This article explains what migraine is, how it differs from tension-type headache, what aura is, and what triggers attacks.

How common is migraine?

The American Migraine Foundation estimates that about 39 million Americans live with migraine. In a large US survey of more than 160,000 people age 12 and older, about 12% had migraine in the past year: about 17% of women and 6% of men. That makes migraine about three times as common in women as in men. Hormone changes, such as those around a period, are thought to be one reason. Migraine often starts in the teens or early twenties and is most common in the middle years of life.

It is also disabling. In the same survey, more than half of people with migraine said their attacks caused severe problems with daily activities or forced them to rest in bed. Worldwide, migraine is the second biggest cause of disability, and the biggest among young women.

Migraine is a real neurological disease

Migraine isn't imagined, and it isn't “just stress.” It is a disorder of how the brain and nearby nerves handle signals. During an attack, nerves around the brain send abnormal pain signals and release chemicals, including a protein called CGRP that helps carry pain signals. Genes play a part. More than half of people with migraine have a family member who has it too.

Doctors diagnose migraine from how you describe your attacks, along with an exam. Brain scans such as MRI or CT aren't usually needed, unless a doctor wants to rule out another cause. There's no cure yet, but treatment can make attacks less frequent and ease them when they happen. Which treatment fits you is a decision to make with your doctor. Learn more in Migraine medications.

How is migraine different from tension-type headache?

Tension-type headache is the most common type of headache. The biggest clues are whether moving makes the pain worse and whether light, sound or nausea bother you.

People with migraine are more likely to get tension-type headaches too, so many people have both.

How doctors define migraine

Doctors use criteria from the International Classification of Headache Disorders (ICHD-3). In plain words, migraine without aura means all of these are true:

• You've had at least five attacks like this.
• Each attack lasts 4 to 72 hours if it isn't treated, or if treatment doesn't work. In children and teens, attacks can be as short as 2 hours.
• The pain has at least two of these four features: it's on one side, it throbs, it's moderate or severe, or routine activity such as walking or climbing stairs makes it worse or makes you avoid moving.
• During the pain, you have nausea or vomiting, or both light and sound bother you.
• No other condition explains the headaches better.

This is how doctors think about migraine, not a test to diagnose yourself. Other conditions can cause similar headaches, so leave the diagnosis to a doctor.

What is a migraine aura?

Aura is a set of nerve symptoms that spread slowly over at least 5 minutes, with each symptom lasting 5 to 60 minutes. It usually comes before the headache, and the headache often starts within an hour. About 1 in 3 people with migraine have aura. Many of them also have attacks without it.

Vision changes are by far the most common: zigzag lines, flashing or shimmering lights, or a blind spot that slowly grows. Next is pins and needles that slowly spread over one hand, arm or side of the face. Some people have trouble finding words. Aura can also happen without a headache.

Call 911 if you have weakness on one side of your body. Also call 911 if symptoms such as trouble speaking or vision loss are new for you, start suddenly, or feel different from your usual aura. A stroke can cause symptoms like these, and only a doctor can tell them apart. See a doctor soon if your aura lasts more than an hour or doesn't go away.

If you have migraine with aura, tell the doctor who prescribes your birth control. CDC guidelines advise against birth control that contains estrogen, such as combined pills, the patch and the ring, for people with migraine with aura. Migraine with aura and estrogen can each raise the risk of stroke. Don't stop your birth control on your own. Talk with your doctor about your options.

The four phases of a migraine attack

An attack can move through up to four phases. Not everyone has all four, and not every attack includes each one.

Learning your own early signs can help. Ask your doctor how to use them to time your treatment.

What triggers migraine attacks?

A trigger is something that can set off an attack in a person who has migraine. Attacks are more likely when several triggers pile up. In a study of more than 1,200 people at a US headache center, about 3 in 4 said something triggered their attacks, and stress was the most common. Other common triggers include:

• Stress, or the letdown after it, such as on a weekend after a hard week
• Too little or too much sleep
• Skipped meals
• Hormone changes, such as around a period
• Changes in the weather (see Barometric pressure and headaches)
• Bright or flashing lights, loud noises and strong smells
• Alcohol

Some “triggers” may be early signs of an attack that has already started. Craving chocolate can be part of the prodrome, so the chocolate gets the blame. Attacks can also come with no clear trigger. If an attack comes anyway, it isn't your fault. Often it's simply the disease.

Episodic and chronic migraine

Chronic migraine means headaches on 15 or more days a month for more than 3 months, with migraine features on at least 8 of those days. Migraine with fewer headache days is often called episodic migraine. Chronic migraine affects about 1 in 50 people worldwide.

Episodic migraine can turn into chronic migraine. In a large US study, about 2.5% of people with episodic migraine developed chronic migraine within a year. Frequent headaches raised the risk. Taking headache medicine too often can also make headaches more frequent. If you take headache medicine, over-the-counter or prescription, on 10 or more days a month, talk to your doctor. See Medication overuse headache.

Why keeping a record helps

Because migraine is diagnosed from your story, a headache record is one of the most useful things you can bring to an appointment. Note each headache day, how long it lasted, how bad it was, and what you took. When headaches are frequent, the classification doctors use calls for a day-by-day diary of at least one month.

With Zutsu Note, you can log headaches and medicines in a few taps and see your headache days each month on a chart. You can also show your doctor a 30-day summary on your phone. If you use Zutsu Note in a web browser, you can print it or save it as a PDF.

When to see a doctor

• Headaches get in the way of work, school or family life.
• You take headache medicine on 10 or more days a month.
• Your headaches are becoming more frequent, or your usual medicine isn't working well.
• An attack lasts more than 3 days. Get care promptly.
• Get emergency care right away for a sudden, severe headache, a headache unlike your usual ones, or a headache with fever, weakness or numbness, or trouble speaking. Call 911 or go to the nearest emergency room. See When to worry about a headache.

A primary care doctor is a good place to start and can refer you to a neurologist if needed. To find a headache specialist near you, try the American Migraine Foundation's doctor finder.

Studies and guidelines we used

• Headache Classification Committee of the International Headache Society. The International Classification of Headache Disorders, 3rd edition (ICHD-3). Cephalalgia. 2018;38:1-211.
• Lipton RB, et al. Migraine prevalence, disease burden, and the need for preventive therapy. Neurology. 2007;68:343-349.
• Launer LJ, Terwindt GM, Ferrari MD. The prevalence and characteristics of migraine in a population-based cohort: the GEM study. Neurology. 1999;53:537-542.
• Kelman L. The triggers or precipitants of the acute migraine attack. Cephalalgia. 2007;27:394-402.
• Bigal ME, et al. Acute migraine medications and evolution from episodic to chronic migraine: a longitudinal population-based study. Headache. 2008;48:1157-1168.
• Steiner TJ, et al. Migraine remains second among the world's causes of disability, and first among young women: findings from GBD2019. The Journal of Headache and Pain. 2020;21:137.
• Nguyen AT, et al. U.S. Medical Eligibility Criteria for Contraceptive Use, 2024. MMWR Recommendations and Reports. 2024;73(No. RR-4):1-126.
• National Institute of Neurological Disorders and Stroke. Migraine; Headache.
• National Library of Medicine, MedlinePlus Genetics. Migraine.
• American Migraine Foundation. The Timeline of a Migraine Attack; The Science Behind Migraine Triggers.