Medication overuse headache (rebound headache)

If you take headache medicine on many days a month, the medicine itself may be making your headaches more frequent. This is called medication overuse headache, or MOH. Many people know it as rebound headache. It's common, it often starts without the person noticing, and it can be treated. This article explains the limits doctors use, who is at risk, and how treatment works.

What is medication overuse headache?

MOH develops in people who already have a headache disorder, most often migraine or tension-type headache. When acute headache medicine is used very often for months, the brain's pain system seems to become more sensitive. Headaches come more often, until there is a headache on 15 or more days a month. More headaches lead to more medicine, and more medicine leads to more headaches.

About 1 to 2 in every 100 people have MOH in a given year. Among people with headaches on 15 or more days a month, more than half have it.

How many days is too many?

Doctors use the limits in the International Classification of Headache Disorders (ICHD-3). What counts is the number of days you take medicine, not the number of pills. A day counts once, however many doses you take that day. Pain relievers you take for other reasons, such as back pain, count too.

Many over-the-counter headache products combine pain relievers with caffeine. These count as combination medicines, with the 10-day limit. To check yours, look at the active ingredients on the Drug Facts label, or ask a pharmacist.

These numbers are where doctors begin to suspect MOH. They aren't a safe target. The American Headache Society suggests using over-the-counter pain medicine for headache on no more than 2 days a week. If your medicine days are rising, talk to your doctor even if you haven't reached the limits.

Signs to watch for

• Your headaches have become more frequent, up to about half the days in a month.
• You often wake up with a headache.
• Your medicine doesn't work as well as it used to, or the pain comes back within hours.
• You take medicine “just in case,” before a headache starts.
• You worry about running out of headache medicine and always carry it.

The surest way to know is to count. Memory isn't reliable for this. Keep a record of your headache days and medicine days for a month, then compare the numbers with the table above. See how to keep a headache diary.

Zutsu Note shows how many days you had a headache and how many days you took medicine each month, so you can compare them with these limits. You can also show a 30-day summary at your appointment on your phone, or print it or save it as a PDF if you use Zutsu Note in a web browser.

Who is at risk?

• People with migraine or tension-type headache who treat their headaches often
• People whose headaches are already frequent
• Women, who get MOH more often than men
• People with depression, anxiety, or other long-term pain
• People who use opioids or butalbital-containing medicines, which the American Headache Society links to migraine becoming more frequent

How is it treated?

MOH is treated with a doctor: your primary care doctor, a neurologist, or a headache specialist. Treatment usually has three parts.

• Understanding the problem. Learning how frequent medicine use leads to more headaches is an important first step. For some people, this advice alone is enough to cut back.
• Cutting back on the overused medicine. Depending on the medicine, it may be stopped or reduced slowly. Your doctor plans this with you, including what to do on bad days.
• Starting prevention. Preventive treatment lowers the number of headache days, so you need acute medicine less often. The 2026 guideline from the American Academy of Neurology and the American Headache Society says it should be offered to people with MOH. See the options in Migraine medications.

Doing these together seems to work best. In a study from Denmark, about 3 in 4 people who cut back and started preventive medicine at the same time were down to fewer than 15 headache days a month after 6 months, compared with about 4 in 10 of those who cut back first and considered prevention later. Newer preventive medicines that target CGRP have also been studied in people with medication overuse, and many had fewer headache days and fewer days of acute medicine.

Headaches may get worse for a while before they get better. This is expected, and your doctor can help you plan for it. Most people improve once the overuse stops, and preventive treatment often works better afterward.

Don't stop on your own

If you think you have MOH, talk to your doctor before you stop or cut back. For some medicines, stopping suddenly can be dangerous.

• Butalbital, found in some prescription headache medicines, can cause dependence. Stopping it suddenly after regular use can cause serious withdrawal, including seizures. It needs to be reduced slowly, with a plan from your doctor.
• Opioids also need a gradual plan. Their FDA labels warn that stopping suddenly in people who depend on them can cause serious withdrawal symptoms and uncontrolled pain.
• Other medicines are often easier to stop, but a plan still helps: what to do on bad days, how to get through the hardest stretch, and which prevention to start.

Gepants and MOH: what we know so far

Gepants are newer migraine medicines. Rimegepant, ubrogepant, and zavegepant treat attacks, and atogepant and rimegepant are used for prevention. The ICHD-3 limits came out in 2018, before the first gepant was approved in the US in late 2019, so they don't mention gepants.

So far, the early evidence is reassuring:

• In a study in rats, repeated doses of ubrogepant did not cause the lasting pain sensitivity that a triptan did.
• In a 1-year safety study of rimegepant for attacks, researchers saw no sign of medication overuse headache.
• Atogepant, used for prevention, reduced migraine days in people with chronic migraine, whether or not they were overusing acute medicine.

But this question is still being studied. Results in animals don't always hold true in people, and a few studies are not the final word. Until more is known, log gepant days the same way as any other headache medicine, and ask your doctor how often it's right for you to use them.

After it gets better

MOH can come back, especially if medicine days creep up again. The risk is highest after opioid overuse. Keep logging your headaches and medicines, and if your medicine days start to rise, talk to your doctor early.

When to see a doctor

• You take acute headache medicine on 10 or more days a month, or a simple pain reliever on 15 or more days a month.
• You have headaches on 15 or more days a month.
• Your headache medicine works less well than it used to.
• You take butalbital or an opioid for headaches. Don't stop on your own. Ask your doctor about a plan.
• Get emergency care right away for a sudden, severe headache, a headache unlike your usual ones, or a headache with fever, weakness or numbness in an arm or leg, or trouble speaking. Call 911 or go to the nearest emergency room.

A primary care doctor can often start treatment, and a neurologist or headache specialist can help if things don't improve. See how to find a headache specialist, or try the American Migraine Foundation's doctor finder. If you're not sure whether a headache needs urgent care, read when to worry about a headache.

Studies and guidelines we used

• Headache Classification Committee of the International Headache Society. The International Classification of Headache Disorders, 3rd edition. Cephalalgia. 2018;38:1-211.
• Diener HC, et al. Pathophysiology, prevention, and treatment of medication overuse headache. Lancet Neurology. 2019;18:891-902.
• Ashina S, et al. Medication overuse headache. Nature Reviews Disease Primers. 2023;9:5.
• Carlsen LN, et al. Comparison of 3 treatment strategies for medication overuse headache: a randomized clinical trial. JAMA Neurology. 2020;77:1069-1078.
• Potrebic S, et al. Pharmacologic treatment for migraine prevention in adults practice guideline recommendations: report of the AAN Guidelines Subcommittee and the American Headache Society. Neurology. 2026;107:e214881.
• Loder E, et al. Choosing wisely in headache medicine: the American Headache Society's list of five things physicians and patients should question. Headache. 2013;53:1651-1659.
• Navratilova E, et al. Ubrogepant does not induce latent sensitization in a preclinical model of medication overuse headache. Cephalalgia. 2020;40:892-902.
• Croop R, et al. A multicenter, open-label long-term safety study of rimegepant for the acute treatment of migraine. Cephalalgia. 2024;44:3331024241232944.
• Goadsby PJ, et al. Efficacy of atogepant in chronic migraine with and without acute medication overuse in the randomized, double-blind, phase 3 PROGRESS trial. Neurology. 2024;103:e209584.
• Tepper SJ, et al. Efficacy and safety of erenumab in adults with medication overuse headache: final results from a phase 4 randomized placebo-controlled study. European Journal of Neurology. 2025;32:e70328.
• US Food and Drug Administration. Prescribing information (DailyMed) for butalbital-containing medicines, opioid pain medicines, and triptans, checked November 2026.