Find a Doctor Find a Doctor
Time to see a specialist? Time to see a specialist?
We found [COUNT] Specialists
who treat [INTEREST]
We found [COUNT] Specialists
who treat [INTEREST]
[TELEHEALTH] offer Telehealth options.
Finding the Right Chronic Migraine Treatment

This content is created by Healthgrades and brought to you by an advertising sponsor. More

This content is created or selected by the Healthgrades editorial team and is funded by an advertising sponsor. The content is subject to the Healthgrades medical review process for accuracy, balance and objectivity. The content is not edited or otherwise influenced by the advertisers appearing on this page except with the possible suggestion of the broad topic area. For more information, read the Healthgrades advertising policy.

Migraines and Botox Injections

Medically Reviewed By William C. Lloyd III, MD, FACS
Was this helpful?

Botox® is approved to prevent chronic migraines in adults 18 years and older. Chronic migraine means that a person experiences a migraine headache for four hours or more on at least 15 days each month. About 3.2 million Americans suffer from chronic migraine. If you’re one of them, you may wonder about using Botox. Use this article as a quick reference for what you need to know.

What Causes Chronic Migraine?

Migraines usually occur periodically from a couple of times a year to a couple of times per week. Some people experience an increase in frequency of migraine headaches that turns into a condition known as chronic migraine. In most cases, this progression to chronic migraine is due to overuse of pain-relieving migraine medication. This is also called a rebound headache. Chronic migraine actually causes structural and functional changes in the brain that make it different from episodic migraine (migraine headache that occurs periodically).

How Does Botox Work for Chronic Migraine?

Researchers don’t fully understand how Botox works to prevent chronic migraine. Botox is a neurotoxin that prevents nerves from releasing a chemical. This chemical tells muscles to contract. If nerves don’t release the chemical, muscles stay relaxed. This is how Botox works to smooth wrinkles and treat medical conditions, such as overactive bladder and eyelid muscle spasms.

This mechanism of action can’t fully explain how Botox prevents chronic migraine. Researchers have a few theories, but they haven’t been able to pinpoint exactly how it works. It could have something to do with Botox blocking pain signals from muscles and nerves back to the brain. This breaks the cycle of the brain being constantly sensitized to pain.

What Evidence Supports Botox for Chronic Migraine?

The FDA (Food and Drug Administration) approved Botox for the prevention of chronic migraines based on evidence from two large studies. These studies compared Botox to a placebo injection. They showed that Botox significantly decreased the number of headache days from baseline. It also decreased the cumulative hours of headache on headache days.

What Should I Consider in Making the Decision?

If you’ve tried other preventive therapies without success, you may want to consider Botox. But first, you need to be sure you suffer from chronic migraine. Botox is not effective in preventing episodic migraine. 

Think about how your headaches are affecting your quality of life. Keep a symptom diary to record the frequency, length and effects of your headaches on your daily life. This will help your doctor know whether Botox is likely to help you.

You should understand that you need to give Botox adequate time to work. It generally takes two sessions 12 weeks apart to see the full effect. Continuing your symptom diary will help your doctor gauge your progress. If it works, you should have a treatment every 12 weeks.

Was this helpful?
Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2020 Sep 9
View All Finding the Right Chronic Migraine Treatment Articles
THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
  1. About Migraine. Migraine Research Foundation.
  2. Botox Prescribing Information. Allergan.
  3. Durham PL, Cady R. Insights into the mechanism of onabotulinumtoxinA in chronic migraine. Headache. 2011 Nov-Dec;51(10):1573-7.
  4. Frequently Asked Questions About Botox. Allergan.
  5. Getting Started. Allergan.
  6. Migraine. The Merck Manual for Healthcare Professionals.
  7. Oliver M, MacDonald J, Rajwani M. The use of botulinum neurotoxin type A (Botox) for headaches: a case review. J Can Chiropr Assoc. Dec 2006; 50(4): 263–270.