Medication-Overuse Headache (Rebound Headache)

What is medication-overuse headache?

Medication-overuse headache (MOH), often called rebound headache, is a chronic daily headache that develops in people who take acute pain medication too frequently over a long period. The headache becomes a side effect of the very treatment used to relieve it — a pattern recognised in the International Classification of Headache Disorders (ICHD-3).

It almost always develops on top of an existing primary headache disorder, such as migraine or tension-type headache. If you're not sure which type of headache you have, our guide to migraine vs tension-type headache is a good starting point.

Why is it called rebound headache?

"Rebound" describes what people notice in practice: the painkiller works for a few hours, the headache returns — often a little sooner each time — and another dose is needed. Over weeks and months, the pain-processing pathways become more sensitive, and the headache settles into a near-daily pattern that's driven by the medication itself rather than the original condition.

Can ibuprofen, paracetamol or triptans cause it?

Yes — and the threshold depends on the type of medicine. The clinical definitions are:

• Simple painkillers (paracetamol, ibuprofen, aspirin, naproxen): more than 15 days per month.
• Triptans (sumatriptan, rizatriptan and others): more than 10 days per month.
• Opioids (codeine, tramadol, morphine): more than 10 days per month.
• Combination analgesics (e.g. paracetamol with codeine or caffeine): more than 10 days per month.
• Ergots: more than 10 days per month.

For all categories, the pattern must be sustained for three months or more. Not everyone who takes these medicines frequently will develop MOH, but anyone with an existing primary headache disorder is at higher risk.

How to recognise the pattern

MOH tends to look different from the headache it grew out of. Common features include:

• Headache on most days, often present on waking.
• Pain medication helps briefly, but the headache returns — usually a little sooner each time.
• The character of the original headache changes — for example, a migraine pattern starts to feel more like a dull, constant ache.
• A sense of being "stuck" between doses, with growing reliance on medication just to function.

The simplest way to see the pattern is to log both your headaches and your medication days side by side. Our guide on what to track in a headache diary walks through this.

Why does it happen?

The exact mechanism isn't fully understood, but frequent use of acute medication appears to change how the brain processes pain — lowering the threshold at which headaches are triggered. In effect, the medication that once relieved the pain begins to maintain it. This is a secondary effect of treatment, which is why MOH is classified separately from the primary headache disorder it grows out of. The distinction between primary and secondary headaches matters here, because the treatment is different.

Breaking the cycle

The recognised treatment is planned medication withdrawal — reducing or stopping the overused medication under medical guidance. Withdrawal is effective, but the right method depends on which medicine is involved, how long it has been used, and your wider health, so it has to be planned with your GP or specialist.

Never stop or change prescribed medication on your own. Nothing on this page is a recommendation to start, stop, taper or substitute any medicine. Preventive treatment and support during the withdrawal period may also form part of the plan your clinician puts together.

Around 20–30% of people relapse within a year (Gosalia et al., 2024), which is why tracking medication use afterwards is just as important as during withdrawal.

How long does recovery take?

Most people experience a temporary worsening of headache in the first one to two weeks as the body adjusts. From there, headaches typically improve over the following two to eight weeks as pain-processing pathways return towards normal. The underlying headache disorder doesn't go away — but it usually returns to its baseline frequency, which is far lower than the daily pattern driven by overuse.

When to speak to a doctor

Consider talking to your GP or a headache specialist if you're taking acute pain medication on more than 10–15 days per month, if your headaches are becoming more frequent despite treatment, or if you're worried about how often you're reaching for painkillers. MOH is common and very treatable — but it needs the right plan rather than another increase in dose.

Bringing a few weeks of tracked data with you makes that first conversation much more useful.