Chronic migraine, when someone has more than 15 headache days per month, affects 3–5% of the U.S. population.

Migraine is a common and disabling condition reported in approximately 12% of the population. In the Global Burden of Disease Study in 2019, migraine was found to be the third highest cause worldwide of years lived with disability. Migraine attacks sometimes increase in frequency over time. Headache experts divide this process of transition into three distinct states:

  • No migraine
  • Episodic migraine
  • Chronic migraine (15 or more headache days per month)

Chronic migraine occurs in 3–5% of the U.S. population. It’s possible for someone with episodic migraine to develop chronic migraine. In addition, studies suggest that about 3% of people with episodic migraine will “transition” to chronic migraine each year.

Read more to learn about the symptoms, risk factors, diagnosis and treatment of this condition.

What Is Chronic Migraine?

The International Headache Society defines chronic migraine as headache occurring on 15 or more days per month for more than three months, where at least 8 of those headache days have migraine features:

  • The pain is moderate or severe and often intense.
  • The pain may be on one side or the head or both.
  • The head pain causes a throbbing, pounding or pulsating sensation.
  • The pain gets worse with physical activity or movement.
  • The patient must have nausea, vomiting, and/or light and sound sensitivity along with the head pain.

The other headache days don’t need to be full migraine attacks. For example, if you have a migraine attack with a severe headache on day one and take medication but still have a low-level headache on day two, that would be one day of migraine headache and one day of other headache.

A recent study published in the journal Headache® found that the current definition of chronic migraine does not reflect major differences in disability faced by patients. The study found that patients with 8–14 headache days a month had similar levels of disability as patients with 15–23 headache days a month. In time, this research, which used data from American Migraine Foundation’s (AMF) American Registry for Migraine Research (ARMR), could help patients get access to treatment based on their level of disability.

What Are the Risk Factors?

Chronic migraine has some common but treatable risk factors. Some examples of risk factors include:

  • Depression
  • Anxiety
  • Other pain disorders
  • Obesity
  • Asthma
  • Snoring
  • Stressful life events
  • Head/neck injury
  • Caffeine
  • Acute medication overuse
  • Persistent, frequent nausea

Download our free guide to chronic migraine risk here.

How Is Chronic Migraine Diagnosed?

If you think you might have chronic migraine, it’s important to speak to a healthcare provider about it. That can be your primary care physician or a headache specialist.

A diagnosis depends on how many headache days you have, rather than the amount of disability you experience. So it’s important to track your headache days. Many people underestimate the number of days they have a headache. That’s because they tend to count the really bad days, while discounting the not-so-bad days. To avoid this, keep a headache journal so you can keep track of all your headache days.

If you only report your most severe headaches, you might give your doctor a false impression of your true headache burden. As a result, they might miss a chronic migraine diagnosis.

If you suspect chronic migraine, you should be carefully assessed by your doctor to exclude other potential causes of frequent headaches. For example, you can have secondary headaches (meaning headaches caused by an underlying condition or disease) or other forms of chronic daily headache. You might also have chronic tension-type headache, hemicrania continua or new daily persistent headache.

How Do You Treat Chronic Migraine?

Treatment of chronic migraine is similar to episodic migraine, but with a few key exceptions. A treatment plan can include acute medication and preventive medication. There’s also non-medication preventive treatments including biofeedback and cognitive behavioral therapy. In addition, addressing risk factors such as depression, anxiety, snoring and obesity can help.

You can take acute medications at the start of a migraine attack to try to break it. These medications include over-the-counter and prescription treatments (like ibuprofen, acetaminophen and sumatriptan, among others). However, it’s important to limit how much you use them to try to avoid medication overuse and risk of medication overuse headache.

Preventive medications help reduce the frequency and severity of headache attacks. Onabotulinumtoxin A (Botox) was the first FDA-approved preventive treatment for chronic migraine and has been shown to reduce the number of headache days per month on average by about 50%. In 2018, the FDA approved anti-CGRP migraine treatments to prevent both chronic and episodic migraine. There is evidence they can reduce the number of migraine days by six to eight days per month for people with chronic migraine.

Preventive treatments used for episodic migraine, such as anti-seizure medications (e.g., depakote, topiramate), antidepressants (e.g., amitriptyline, venlafaxine) and blood pressure medications (e.g., propranolol), may also serve to prevent chronic migraine.

Medication should be one aspect of a complete migraine plan. Things like biofeedback and acupuncture can complement medication. Taking care of yourself, like getting enough sleep and drinking plenty of water, should also be part of your migraine management plan.


The American Migraine Foundation is committed to improving the lives of those living with this debilitating disease. For more of the latest news and information on migraine, visit the AMF Resource Library. For more on advocacy and ways that you can get involved, please visit our Advocacy Hub.