Medication Overuse Headache

Migraine and headache disorders affect millions of Australians. Some people might find that they can treat their attacks with acute medication such as paracetamol, ibuprofen, or triptans. But if these medications are taken too often, they can actually cause medication overuse headache.

This refers to the worsening of an existing migraine or headache disorder – attacks can be more frequent, more severe, and/or harder to treat. Learning about safe medication dosages and alternative treatment options (like preventive medications) can help you avoid medication overuse headache.

In this article:

  • Chronic Daily Headache
    • Migraine
    • Tension-type Headache
  • Other Rare Headache Types
    • Cluster
    • Hemicrania Continua
  • Medication Overuse Headache (MOH)
    • Characteristics
    • Risk Factors
    • Causes
    • Safe Limits Of Medication Use
    • How To Manage MOH
    • Greater Occipital Nerve Blocks
    • In-patient Treatment
    • Treatment Path For Patients With MOH
    • Acute Treatment
    • Behavioural And Lifestyle Factors

Medically reviewed by Nicole Limberg, MD. Last updated 8 July, 2020.

Watch the full presentation recording

This article was adapted from a presentation by Dr Nicole Limberg, originally presented during Migraine & Headache Awareness Week 2019.

Neurologist and Director of Migraine Specialist in Spring Hill, Brisbane. The clinic specializes in the treatment of chronic migraine, including the provision of botulinum toxin therapy. Dr. Limberg has participated as an investigator in further research of chronic migraine therapy, and provides training and education on the topic of chronic migraine therapy to her medical colleagues. She is also dedicated to improved patient education and contributes to a regular blog at Dr. Limberg is a member of the Australian and New Zealand Association of Neurologists (ANZAN), as well as the newly formed Australian and New Zealand Headache Society (ANZHS).


Chronic Daily Headache

Headache is one of the top 10 reasons why someone visits the doctor.

Migraine is diagnosed according to the International Classification of Headache Disorders version 3.

Medication overuse headache is a subgroup of migraine which involves chronic daily headache.

Chronic daily headache includes various types of headaches with the three most common being chronic migraine, chronic tension type headaches and medication overuse headache (MOH) formerly known as rebound headache.

Neurologists will often see patients who have subgroups or parts of different conditions. For example someone can have both chronic migraine and medication overuse headache. In fact it is common that these two conditions often occur together.

Unfortunately doctors are not able to use diagnostic tests like a blood test or an MRI to definitively diagnose your exact headache type. The only way to diagnose headache and migraine is by talking to the patient and obtaining a detailed history in order to make an accurate diagnosis or assessment.

There are hundreds of different headache types. The International Classification of Headache Disorders has written an 180 page manual listing the headache types, definitions, characteristics and criteria for diagnosis.


The most commonly debilitating headache disorder of them all is migraine.

The above criteria reveal characteristics of migraine which are asked to the patient to confirm a diagnosis. Is the headache predominantly on one side? Patients will often say it is one sided being mainly on either the right or the left, however it can be both sides.

The pain of migraine is often referred to as being very severe and throbbing and pulsating. Patients may say they can feel the pulse. Migraine is not just a headache, it is a very severe pain that is also accompanied by other disabling symptoms. During an acute attack migraine can worsen with exertion. It can also cause nausea, vomiting or light and noise sensitivity. Photophobia refers to light sensitivity and phonophobia refers to noise sensitivity. These are the common features of migraine that clinicians look for to make a diagnosis.

Within migraine, there are further subtypes. The two main types are migraine with aura and migraine without aura.

Migraine with aura

About 30% of those with migraine experience migraine with aura. The majority of patients do not experience an aura with their migraine attacks. Patients can still have light and sound sensitivity during a migraine attack, but this is different to the aura that affects the 30%.

migraine with aura

Migraine with aura is characterised by temporary visual, sensory, speech or motor symptoms that usually precede the migraine attack.

The most recognisable symptom is the visual aura which affects vision. A scintillating scotoma refers to visual stimuli (such as lights, shapes or patterns) moving across the patient’s field of vision.

The visual aura in some people has inspired them to create art from their experience throughout the ages. This has led to exhibitions in galleries around the world of migraine art.

The visual aura slowly moves across the field of vision in patients for around 20-30 minutes before the onset of headache.

Whilst the visual aura is the most common phenomenon, people can experience other symptoms. Common other symptoms of aura include numbness in the extremities such as the fingers, lips or nose and sensory tingling. Others may experience speech disturbances or not being able to speak or comprehend their situation. In more severe cases, patients can experience motor or muscle weakness.

It is not uncommon for people to have more than one type of migraine and different symptoms across different attacks. For example, someone may have migraine with aura, but they may have different types of symptoms with different senses being affected such as sensitivity to light, sound, smell, touch and they can mix around.

Someone who suffers migraine with aura may also have migraine attacks without aura on different attacks.

Tension Type Headache

Tension type headaches are another very common headache type.

This headache type is typically on both sides of the head (bilateral) and often described as a pressing, squeezing and bandlike pressure or pain around the head.

Generally tension type headache results in a mild to moderate pain level. They do not inhibit daily life to the extent of a severe migraine attack which often leaves patients bed-bound. Patients will say that they are milder and that they can continue with their day-to-day activities. Tension type headaches are not typically associated with nausea and vomiting.

Headache specialists tend to see more of the severe or chronic headache types such as migraine. The general practitioner may see more tension type headache patients.

Rare Types of Primary Headache

Primary headache refers to headache occurring without an obvious cause. Secondary headache is a headache caused by another condition, for example a stroke or a brain tumor or something like that.

A primary headache like migraine for example has no underlying structural cause. Both migraine and tension type headache are types of primary headache disorders.

There are other rarer types of headache that also exist. These include cluster headache and hemicrania continua.

primary headache

A typical cluster attack involves one-sided (unilateral) autonomic symptoms such as tearing, conjunctival injection, nasal discharge or runny nose.

Autonomic symptoms are a constellation of symptoms where the patient can get a red eye, tearing from that eye, a watery nose, a small pupil and possibly a droopy eye lid (ptosis). During a cluster attack you can actually see people looking like this image shown above.

Doctors will ask patients if they have any of these features. Do your eyes appear red? Do you suffer with a watery nose?

It has been shown that migraine patients may experience some degree of these symptoms but not strictly on one side, and not typically of this severity. Doctors look for definitive characteristics that help them determine the difference between migraine and cluster headache. One of these is the agitation felt by the patient during an attack. With migraine patients, they often feel the need to retreat to a dark, quiet room. In a cluster attack, patients may feel agitated and find it difficult to sit still.

The other interesting fact about cluster headache is that they have a distinct timeframe to migraine. Migraine will typically last four to 72 hours. A cluster headache is shorter. It lasts from 15 minutes to three hours and can happen at regular times around the clock. Those with cluster headache will often say at 3:00 am in the morning, “I have a headache lasting for two hours.” They get up and get on with the day, then 11:00 am there’s another one, then 3:00 pm. There appears to be a typical circadian pattern to them.

Those with migraine may reveal that they’ve had a migraine in the middle of the night, but they will not necessarily talk about the regularity that a cluster patient will have.

Hemicrania Continua

Hemicrania continua can look like migraine, there can be an incessant constant headache which does not obey the 15 minutes to three hour rule and it can also cause autonomic symptoms mentioned previously.

Fortunately, hemicrania continua responds exquisitely to a drug called indomethacin, which is a type of anti-inflammatory. It is important not to miss this headache type because it can be effectively treated with a simple tablet. Clinicians ask about these autonomic symptoms to help determine the headache type. Cluster headache and hemicrania continua are rare, but they are treated very differently.

Medication Overuse Headache (MOH)

Medication overuse headaches is a subgroup of headache and it is important to those with migraine and tension type headache. Those with migraine and tension headache are the only patients that experience this condition.

MOH was actually first reported in 1951, and it was described as chronic relentless headache in a subgroup of patients that had migraine and tension headaches already. When these analgesic medications were withdrawn from patients, it led to fewer headaches. It did not cure their headache, but they had a lower frequency of headache. Researchers found that the overused medication was making the patient’s underlying condition worse.

Virtually all acute medications that are used to treat headache can cause this condition, including simple treatments like paracetamol and many other over the counter medications.

MOH can be subclassified by drug type. These classes include triptans, simple analgesics (pain relievers), opioids, or combination treatments.

Overuse of acute medications can lead to:

  • Increase of headache frequency and,
  • Can make headache disorders less responsive to preventive treatments.

The evidence strongly suggests that MOH can make an already difficult situation difficult to treat or even worsen the condition. The very treatment that patients are looking to for relief can actually worsen their situation quite dramatically.

MOH can increase headache frequency and make the disease even less responsive to a management strategy, including some preventive treatments. MOH can be a difficult and expensive condition to treat because it makes everyone’s job harder and the condition less responsive.

There are studies that show that MOH is expensive to treat because there are more sick days, loss of productivity, medical costs, medical appointments to attend, emergency department admissions, and higher levels of utilization of the medical system.

ICHD definition of medication overuse headache

ICHD-3 criteria for MOH is shown above.

The challenge with this criteria is that it could easily fit the criteria for someone with chronic migraine. To diagnose MOH, you have:

  • headache occurring on more than 15 days per month
  • you’re taking medications on those days, and
  • you’ve been doing it for more than three months.

If you are experiencing these symptoms, you could potentially have medication overuse headache. MOH can sit on top of an underlying migraine or tension headache condition which has the potential to make things worse.

Studies have shown that patients without migraine taking regular analgesics for non-headache related conditions like rheumatoid arthritis or osteoarthritis do not typically experience MOH. It seems as though you have to have migraine or tension headaches before you are at risk at developing MOH. Even treating non headache pain, if the patient has migraine, then MOH can still occur. MOH is believed to only develop in primary headache patients who display frequent symptomatic medication use.

Characteristics of MOH

  • Women affected more often than men
  • Most commonly seen in those aged 40 to 45
  • Most common headache diagnoses before MOH are
    • Migraine (65%)
    • Tension type headache (27%)
    • Mixed/ other headache (8%)
  • Tend to occur in the morning due to overnight drug withdrawal or non-restorative sleep
  • Neck pain is also a common symptom in MOH that usually improves with drug withdrawal

Patients with MOH say they often wake up with these headaches and they’ll say, “I take my last headache tablet before I go to bed.” For example, let’s say it’s a triptan and they wake up typically in the morning with the headache. That can happen night after night after night. This is a typical story of what happens typically due to withdrawal of the drug overnight.

Interestingly, patients with medication overuse headaches often suffer neck pain as well, which settles down not uncommonly when the drug is withdrawn.

Central sensitization refers to the chronic stimulation of sensory pathways within the brain which can lead to expansion of the headache area and extreme sensitivity to touch (cuetanous allodynia). Those with chronic migraine and frequent medication use are at a higher risk of developing central sensitization. Patients may say, “I can’t tolerate my sunglasses on my head for too long or I can’t tolerate brushing my hair, it just really hurts, or even when I’m lying on the pillow, it really hurts”. This stimuli that is normally not painful in the setting of medication overuse headache can actually be painful for these patients because of these pathways being amplified.

Many chronic migraine patients may say they are intolerant to light or certain smells i.e. “I’ve never been able to get out in the bright sunlight” or “Strong perfumes bother me.” Certain sounds or loud sounds can also be similarly uncomfortable for those with central sensitization. The symptoms follow a similar process that involves sensory pathways which are chronically amplified and agitated and they become inherently sensitive environmental stimuli that we encounter in our daily life.

When those pathways are stimulated excessively it can trigger a headache or bring on a migraine attack.

When the offending medication is removed and the MOH condition is resolved we see the pathways involved in central sensitization also settle down which has been shown in MRI imaging.

Risk Factors of MOH

Patients with the following risk factors have an increased likelihood of developing MOH:

  • Have a headache frequency of 7 to 14 days per month at baseline
  • Are under 50 years of age
  • Have a history or have been diagnosed with migraine
  • Have any chronic musculoskeletal complaints such as fibromyalgia
  • Have anxiety or depression
  • Experience insomnia
  • Smoke
  • Are not physically active

There is a well established link between anxiety and depression and chronic pain in general, poor sleep, smoking and being physically inactive. These risk factors are important to consider because when a clinician is looking at addressing someone’s medication, they will look at some of those factors to see if any of them can be modified.


We know that those with migraine are inherently sensitive within their sensory pathways to stimuli and analgesic medication can amplify this stimuli. This central sensitization pathway is something we know about, but there’s still a lot we don’t know.

Genetic factors may play a role. The risk of MOH is almost three times greater in those with a family history of MOH. There may be some behavioral factors involved. Patients may often say to the clinician they use medications sometimes even when they are not necessarily suffering a headache, but they’ve got something important that they have to go to or do, and they’ll take the medication almost in anticipation of the migraine before it has begun. Fear of headache may perpetuate MOH.

There is also a great lack of awareness of MOH amongst both patients and health care professionals. Many people simply may not understand how acute medications for pain can lead to a worsening of their condition if not taken appropriately.

MRI studies have shown that when you take the offending drugs away, there is a reversible nature of this condition. MOH is reversible, it is curable in that sense. The underlying migraine condition is not necessarily curable at this stage, but this MOH component of it certainly is reversible with cessation or withdrawal of the drug.

MOH can occur from many different drug categories. For example, a patient taking Panadol every day diligently thinking they’re doing the right thing to prevent getting a migraine may be exacerbating their condition. Patients can be quite shocked to realise that a drug such as Panadol could be causing this.

Just having this discussion between the patient and doctor and discovering that the very thing that the patient is doing is likely making things significantly worse, is often very helpful and may be all that is needed.

Safe Limits of Medication to Avoid MOH

What are the limits that can be taken to avoid falling into the trap of MOH? The answer varies according to what treatment class is being taken. The important distinction to understand is the number of days when you take the medication, rather than the number of doses taken, is what is counted below.

Drug Class Recommended Dosage Limit
Simple Analgesics (Aspirin, Acetaminophen, Paracetmol, Ibuprofen, Naproxen) Less than 10-14 days per month
Over the counter (OTC) caffeine containing analgesics Less than 10 days per month
Triptans Less than 10 days per month
Narcotics Totally avoid

With simple analgesics, which largely you can buy over the counter, you can get away with up to 14 days per month that you can take the medication. That’s every two to three days per week, but once you go beyond this frequency, studies suggest you may run the risk of MOH. Not everyone with migraine experiences MOH but they certainly are more likely to experience it than the average population.

If caffeine containing painkillers are taken, then the limit is no more than 10 days per month. Caffeine can be known to cause a withdrawal headache.

The triptans are an effective treatment for the acute migraine attack but if they are overused they can make the migraine condition significantly worse. The limit of triptans is also no more than 10 days per month.

How to Manage MOH

In some cases, patient education to let them know their safe limits is simply all that is required. However, if there is a dependence on the drug, things can get more complicated, especially if the drug is a narcotic like endone or codeine.

Unfortunately there is no universal consensus on how to treat patients with MOH.

There was a study in 2018 that essentially showed that a complete stop of acute medication during a two month detoxification period was the most effective treatment in terms of percentage reduction in headache days per month, six months after the intervention. This approach was compared to a program where they had restricted drug use to no more than two days per week.

The group that stopped all acute medicinal treatments and worked on other techniques such as pain management or cognitive behavioral type techniques did better.

The challenge is that patients can’t always afford to do a complete detox in the real world. They have jobs, they’re raising children, they’ve got lives to lead and they just can’t go in a facility to have two months off to complete this detox program. In many cases it may not be practical.

What some clinicians may offer to their patients who are still leading full lives is a restricted program. The patient is educated and given guidelines on what they can take, but the analgesics can still be taken in a restricted quantity. This compromise can still be a very effective approach.

What happens when you’ve been taking a triptan like Imigran every day or you’ve been taking Panadol every day and you decide to reduce it? What happens when you have 10 cups of coffee every day, and you stop drinking coffee? In both cases you can have withdrawal symptoms occur. Withdrawal symptoms do not occur in every MOH patient. They occur most frequently in patients on opioids but less so on triptans and anti inflammatories. Typically, withdrawal symptoms don’t last beyond four weeks. Fortunately many withdrawal symptoms last from two to 10 days.

As a patient you might think “I’ve got to keep working and I’ve got to keep looking after these children and I’ve got to keep up my responsibilities.” This option provides a bridge in the therapy when the patient is withdrawing from their offending treatment and restricting their quantities.

There are several options that can be used during this bridging phase to help patients get through the withdrawal period.

Naproxen, which is a long acting anti inflammatory, has good evidence for use during this period. It is a long acting treatment that can be used as a rescue treatment. We also interestingly have evidence from anti nausea medications like Stemetil and Maxolon. Many people don’t realize that those drugs as well as having anti-nausea effects also have pain relieving effects.

Interestingly, as mentioned above, nearly all drugs can cause MOH, but Stemetil and Maxolon have not been shown to cause MOH which may be very helpful for some patients.

Naproxen, Stemetil and Maxolon are all useful. There are more options available. Steroids have been studied and have been found to be helpful. The studies vary in the quality of results but overall they are seen as helpful. Occipital nerve blocks are also another option which we explore below.

During the withdrawal period, headache can initially get worse as less medication is taken and people can also experience nausea or vomiting. They can also experience some sleep disturbances or they may feel more restless, nervous or anxious. These are a few types of withdrawal symptoms that people can experience in this two week withdrawal period, and that’s what is sought to offset with some of those therapies mentioned above.

If a patient is withdrawing from a narcotic, then an inpatient treatment may be required.

Greater Occipital Nerve Blockade

A greater occipital nerve blockade (GON) can be particularly useful when anticipating an upcoming withdrawal period due to medication overuse headache. Relief can be rapid with few adverse effects.

This is a procedure that occurs in the doctor’s office which can be very helpful. Often patients will say that the pain starts from the back of their neck and it moves forward. There are many nerves in the back of the head called occipital nerves. These may be the origin of some of these pain signals for a lot of patients.

Nerve blocks can be used for a severe migraine attack. Essentially a steroid and anesthetic formulation is injected into these nerves at the back of the head. These injections can be performed as an outpatient and can help facilitate a withdrawal from MOH without having to stay at a clinic or hospital as an inpatient.

There are a couple of situations where admitting a patient may be required:

  • Severe depression
  • Opioid use

Withdrawing from opioids can be very difficult to do as an outpatient. Inpatient monitoring is safer and more effective in this case. For those with an opioid dependence and severe depression or other mental health issues they would typically be referred for an inpatient pain review and detoxification program.


In the treatment of MOH we’ve covered the provision of education, setting limits and guidelines on what can be taken, bridge therapy, long acting anti-inflammatories and a GON block. The other strategy to consider is starting a preventive.

Many patients are not on any medications to help prevent headaches from occurring in the first place.

People can be easily trapped in a cycle of headache-treatment-headache with MOH. Preventive therapies are another important tool to break this cycle.

When a preventive treatment is used, chronic migraine and MOH often revert to episodic headache.

There are various preventives available including:

  • Blood pressure medications
  • Anti-epileptics
  • Anti-hypertensives
  • Onabotulinum toxin (Botox)
  • Anti-CGRPs

Each clinician may have their own personal experiences and preferences with these options.

There are occasions where patients will have another condition or disease where certain drugs may be beneficial to consider. This requires an individual approach based on a discussion between the clinician and the patient.

When looking at the evidence of what has worked or what has been beneficial in medication overuse headaches, three options come up frequently. These are:

  • Topiramate (brand name Topamax)
  • Onabotulinum toxin (Botox)
  • Anti-CGRPs

Topiramate has been shown to be beneficial for MOH and for use while withdrawing. The drug may, however, cause side effects in some patients.

Onabotulinum toxin (Botox) does have evidence to support its use. When Botox was placed on the Pharmaceutical Benefits Scheme for chronic migraine, studies demonstrated benefit in subgroups of patients that were overusing medications. Onabotulinum toxin is very well tolerated, it also has a very low drop-out rate.

A new class of drugs called the CGRP monoclonal antibodies is also  an effective treatment to be considered. They are also very well tolerated and have low drop off rates.

Preventive treatments are an important part of the overall management plan. It’s not often as simple as withdrawing the acute overused medication and the MOH condition resolves.

Risk factors mentioned previously included a lack of exercise, poor sleep, stress, weight, diet, mood disorders and smoking. Addressing all these things is important in these patients with MOH.

In-patient Treatment

Some people will require inpatient management. These are often patients with MOH for whom outpatient programs have been unsuccessful or for those who overuse opioids.

Withdrawing from opioids without medical supervision can cause seizures, hallucinations, and other more severe symptoms. Severe depression or other health conditions can also add to this risk. In these cases patients are typically referred to a specialist’s in-patient program to specifically manage this withdrawal period as treatment is transitioned into a more sustainable management plan that does not cause further harm to the patient. These inpatient programs are delivered in a supervised and safe setting that facilitate an improved management of withdrawal symptoms.

Treatment Path For Patients With MOH

The above flowchart outlines the key steps that have been discussed in the management of MOH. To summarise:

  • A history is taken to identify if the patients is overusing medications
  • If the patient is overusing opioids or similar narcotic treatments or has other severe conditions then they are immediately considered for inpatient treatment.
  • If the overused medication is something like simple analgesics or the triptans, this can be done as an outpatient.
  • Patient education and discussion may suffice for some patients.
  • There are a few options to consider when withdrawing medications, these include:
    • Complete detoxification
    • A restricted intake program using different acute medications such as Naproxen or some of the anti nausea medications which have demonstrated pain relieving properties.
  • Prevention is then covered with the patient which has two components. Medical and behavioural
    • Medical: Studies have shown evidence to support at least these three options (see above) for use during MOH. These are designed to be taken proactively to prevent or reduce the frequency of migraine attacks.
    • Biobehavioural: These are prevention strategies which have been shown to help reduce and prevent migraine. They include trigger management, regular exercise, stress management, cognitive behavioural therapy and biofeedback.

If a patient fails to respond, tolerate or adhere to treatment then inpatient treatment may be considered.

How to Prevent MOH

How can MOH be prevented before it starts? Awareness is a big part of the answer. Awareness amongst patients, the public, GPs and health care workers such as pharmacists are important for prevention.

In a cohort of medical undergraduate students, 77% were not aware that MOH existed. After learning about MOH, 80% of the students stated they would reduce pain medication consumption of their patients and 83% felt that medication bottles should warn against MOH.

Having a discussion with your GP is another important way to help prevent MOH. If there is an escalating use of analgesics, have a discussion with the GP and request a migraine management plan.

Acute Migraine Treatment

What can be taken for migraine?

Use acute headache treatment within the frequency limits (see above table) to prevent MOH. More targeted migraine therapy such as triptans (such as Imigran or Relpax) and antiemetics (anti nausea medication such as Stemetil, Maxolon i.e. metoclopramide prochlorperazine) should be considered for more disabling attacks.

For mild attacks, non-drug therapies can play a role. Treatments that may be helpful include going for a walk, doing some relaxation therapy, increasing your fluids, using the hot packs or ice packs.

Optimising your behavioural and lifestyle factors which have been previously mentioned is important. These include:

  • Regular exercise
  • Mindfulness based approaches
  • Stress management
  • Management of triggers
  • Reducing alcohol
  • Optimising sleep patterns
  • Avoid skipping meals
  • Regular hydration

Applying these self-driven principles of migraine management will increase the likelihood of success. Many of these elements can be managed or modified to improve overall health and wellbeing and the underlying migraine condition.

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