Chronic daily headache (incorporating chronic migraine and medication overuse headache)

• What is chronic daily headache?
• Statistics on chronic daily headache
• Risk factors for chronic daily headache
• Progression of chronic daily headache
• Symptoms of chronic daily headache
• Clinical examination of chronic daily headache
• How is chronic daily headache diagnosed?
• Prognosis of chronic daily headache
• How is chronic daily headache treated?
• Chronic daily headache prevention
• References

What is chronic daily headache?

Chronic daily headache is a type of frequently occurring headache which may be further classified as
either:

• Chronic migraine, previously known as transformed migraine, is a condition where episodic migraine-type headaches occur more frequently until the individual experiences a migraine on ?15 days per month; or
• Medication overuse headache, which refers to a headache syndrome in which an individual who previously experienced episodic primary headaches does so with increasing frequency, and is unable to achieve appropriate pain relief with normal medication doses. Medication use thus increases and, paradoxically, contributes to headache pain.

Chronic daily headache is thought to most typically occur as a result of medication overuse. The increasing severity and frequency of headache symptoms is usually a withdrawal effect of addictive pain killers (e.g. aspirin, codeine) used to treat migraine or other types of primary headache (e.g. cluster headache). Frequent and regular use (and particularly overuse) of medications used to treat headaches can induce headaches and increase the individual’s requirement to use medication. However, some argue the order of events is reversed and that increasing frequency of headaches results in overuse of medication, rather than vice versa.
Chronic daily headache may also occur without medication overuse, when tension-type, cluster or migraine headaches become more frequent and intense. Some individuals with chronic daily headache who overuse medications fail to improve with withdrawal of the addictive medication, suggesting that medication overuse did not influence the onset of their chronic daily headaches.
Medication overuse and chronic migraine headaches, although once considered the same condition, are now diagnosed according to separate criteria. They are alternative subtypes of chronic daily headache. Chronic migraine is a relatively new term, which replaces transformed migraine and refers to headaches which are predominately migrainous in nature and occur in individuals who do not overuse pain relief medications. Those who overuse medication should not be diagnosed with chronic migraine but with medication overuse headache.

Statistics on chronic daily headache

Only individuals who experience episodic migraines or other types of primary headache are at risk of chronic daily headache. Amongst individuals who experience episodic migraine headaches, one study reported that episodic migraines transformed to chronic migraines in 2.5% of the group. Other studies have reported a higher rate of transformation to chronic migraine of 3%. Amongst individuals accessing treatment at specialist centres (e.g. pain management or headache centres), the rate of progression from episodic to chronic migraine is 14% annually.

Medication overuse headache

Medication overuse headache is the most frequent type of daily headache, accounting for 90% of all chronic daily headache syndromes. It is the reason for some 25–64% of presentations to specialist headache centres.One study estimated that 1% of the adult population and 0.5% of the adolescent population experience medication overuse headache.

Risk factors for chronic daily headache

Chronic daily headache occurs in individuals with a history of a primary headache syndrome. Those who experience more frequent headaches have a greater risk of developing the condition. Other factors which increase the risk include:

• Female gender: For example, one study reported women using non-steroidal anti-inflammatory drugs (NSAIDs) (e.g. aspirin) had a 13.6 times increased risk of developing chronic daily headache and those using triptans (a type of pain killer frequently used to treat migraine) had a 2.9 times increased risk compared to men using these medications;
• Increasing age: The condition occurs most frequently in individuals aged 40–50;
• Arterial hypotension (low blood pressure in the arteries): Has been associated with the transformation of episodic to chronic migraine;
• Psychiatric disorders, particularly major depression and anxiety disorders, are more common in individuals who experience chronic daily headaches;
• Insomnia;
• Obesity;
• Caffeine overuse;
• Stress;
• Cutaneous allodynia, that is pain resulting from stimuli that would not normally cause pain, for example brushing the hair;
• Snoring.

Chronic migraine

The key factor which predisposes an individual to chronic migraine is a long history of chronic primary headache (several years). While chronic migraine may occur in individuals with a history of cluster or tension-type headaches, it most frequently occurs subsequent to migraines.

Medication overuse headache

Individuals with medication overuse headache also have a long headache history. Over 80% of individuals receiving treatment for chronic daily headache have associated medication overuse. Those who use barbiturate or opioid containing medicines have an increased risk of developing medication overuse headaches, and the risk with barbiturates is dose-related (the more barbiturates used, the greater the headache risk). Using NSAIDs for headache pain relief, conversely, reduces the likelihood of transformation medication overuse headache for individuals with a low to moderate number (< 15) of monthly headaches. Some 10% of individuals who regularly use pain relief medications for non-headache conditions (e.g. arthritis) also develop medication overuse headaches. Family history of headache is also a risk factor for developing medication overuse headache, regardless of the individual’s headache history.

Progression of chronic daily headache

Chronic daily headache typically is thought to occur as a withdrawal effect upon cessation of addictive or habituating medications. It may also be termed rebound headache, or, preferably, medication overuse headache.
In Australia, chronic daily headache typically develops in patients with long term use of opioid-containing medications, however any of the medications used to treat headache can cause chronic migraine with overuse. Regular overuse of these medicines or simple analgesics (e.g. paracetamol) for as little as 3 months may also cause chronic migraine. Chronic migraines may also occur after long term correct use, for example:

• Opioids-following at least 4 years of twice weekly use;
• Ergotamines (e.g. Dihydergot) – following at least 2.5 years with twice weekly use; or
• Triptans – following at least 1 year when used three times per week.

The mechanism through which migraine medications cause habituation is not well understood and differs depending on the type of medication. NSAIDs, paracetamol, codeine and dihydrocodeine are thought to cause rebound headaches through altering the neurological pathways involved in pain responses, while combination analgesics containing codeine or caffeine appear to cause such headaches due to their addictive properties.
Individuals with chronic migraine experience 20 headache days per month on average, and on 15 of these days a migraine-type headache is experienced.

Symptoms of chronic daily headache

When a person attends a doctor’s office with headache symptoms suggestive of chronic daily headache, the doctor will conduct a thorough clinical history assessment, with the aim of distinguishing chronic daily headaches from other possible headache diagnoses. Some causes of headache are life-threatening and require urgent treatment and it is important to exclude these conditions. Once the diagnosis of chronic daily headache is made, the doctor will determine whether the diagnosis is chronic migraine (no medication overuse) or medication overuse headache.
The doctor will base their diagnosis primarily on the responses you give to questions about your headache and medication use history. Always be honest when discussing these with your doctor and give the most detailed and accurate information possible. To increase accuracy, it might be a good idea to keep a headache diary, in which you record your headache symptoms, the treatments you use and how you respond to the treatment. Recording these features in a diary for at least 1 month provides accurate evidence for the doctor to make their diagnosis, and can also provide a baseline headache frequency against which the effectiveness of treatments can be assessed.

Chronic migraine

To receive a diagnosis of chronic migraine, you must fulfil the following criteria:

1. Experience regular migraine or tension-type headaches on ?15 days per month, and have done so for at least 3 months;
2. History of ?5 headache attacks fulfilling the criteria for migrainewithout aura. The quality of pain which characterises migraine headache is different to the pain of other headache types;
3. Have been treated with, and responded to, triptan or ergotamine therapy before the development of chronic migraine (criterion 4);
4. Experienced ?8 headaches per month for at least 3 months which have been characterised by at least two of the following pain characteristics (a-d) as well as at least one of e or f:
   a. Unilateral;
   b. Pulsating;
   c. Moderate or severe;
   d. Aggravated by or causing you to avoid routine physical activity; AND
   e. Nausea and/or vomiting; OR
   f. Photophobia (light sensitivity) and/or phonophobia (sound sensitivity).
5. No history of medication overuse;
6. Headaches not attributable to a secondary cause.

Medication overuse headache

To fulfil the diagnostic criteria for medication overuse headache, you must have:

• Experienced headaches for an extended period, usually years;
• Experienced regular headaches on ?15 days per month (if you have a history of migraine or tension-type headaches), or experienced an unremitting cluster of headaches for a duration of ?1 year (if you have a history of cluster headaches);
• Regularly overused medications for migraine treatment for more than 3 months. Regular overuse is defined as:
  • Acute treatment on >15 days per month with simple analgesics (alone or in combination);
  • Acute treatment on >10 days per month using any of the following medications:
    • Ergotamines;
    • Triptans;
    • Opioids;
    • Combined analgesic medications (e.g. simple analgesics with opioids or caffeine);
• Experienced worsening of headaches whilst treating with medicines.

Frequency of dose is more important than overall quantity of medication when considering the likelihood of medication overuse headache. If you take large medication doses once a week, you are less likely to develop medication overuse headache than if you take small doses every day. Medication overuse headache occurs once you develop tolerance to the drug and need to increase the medication dose to achieve pain relief. When the doctor asks about the medications you use, be sure to discuss all of the prescription and over-the-counter analgesics you use, not only for headache pain relief but also for the relief of other types of pain. Tell the doctor whether or not the drugs are becoming less effective or need to be taken in higher doses.
The quality of pain which characterises medication overuse headache differs depending on the type of primary headache disorder from which chronic headaches developed. Individuals who develop chronic headaches subsequent to overuse of medication to treat migraine typically experience persistent migraine-like headaches. These are characterised by unilateral (on one side of the head), pulsating pain with disturbances of the autonomic nervous system (controls involuntary functions such as heartbeat and perspiration). Individuals who overused medications for cluster headaches are also likely to develop chronic headaches characteristic of migraines, which tend to be most severe upon waking. When headaches develop from overuse of medications to treat tension-type headaches, the pain is typically a constant, pressing and diffuse headache, similar in nature to tension headache.
Other symptoms commonly experienced by individuals with medication overuse headache include:

• Asthenia (lack of strength);
• Nausea;
• Restlessness;
• Irritability;
• Depression;
• Difficulty concentrating; and
• Memory problems.

In individuals with pre-existing tension-type headaches, psychiatric and mood disorders are more
common.

Clinical examination of chronic daily headache

Chronic daily headache is diagnosed based on your answers to the doctor’s clinical history assessment. There are usually no obvious physical abnormalities and physical examination is usually not necessary to diagnose the headache. If medication overuse headache is suspected, the doctor may conduct an examination to check for side effects of chronic medication use, including anaemia and gastric ulcers.

How is chronic daily headache diagnosed?

It is not necessary to conduct tests to diagnose chronic daily headache. The doctor may use tests including brain imaging if they suspect your headache is a type of secondary headache.

Prognosis of chronic daily headache

Chronic daily headaches are amongst the most severe and challenging types of headaches to treat, and are associated with significant disability for the individuals who experience them. The degree of disability experienced by an individual with chronic daily headache is significantly worse than that experienced by an individual who experiences episodic headaches.

Chronic migraine

One study which compared individuals with chronic migraine and those with episodic migraine reported a significantly greater degree of disability and impairment in the chronic compared to the episodic group. Individuals with chronic migraine experienced more headache days, were absent from school or work as a result of migraine more frequently and experienced a greater degree of impairment in their daily lives. They were also more likely to be categorised with severe disability using the Migraine Impairment Disability Assessment Scale (a test used by doctors to rate how severely a person’s life is affected by migraines).

Medication overuse headache

Individuals with medication overuse headaches typically fail to respond to acute treatments, worsening the disability associated with the syndrome. Withdrawal of the offending medication is essential to enable effective pharmaceutical treatment in the future and successful withdrawal is defined as a reduction in the number of headache days the person experiences of ?50%. 72% of people with medication overuse headaches achieve withdrawal within 6 months. Successful withdrawal is more likely in individuals with:

• Shorter duration of medication overuse;
• Triptan use, compared to use of other migraine medications;
• Chronic migraine compared to other types of headaches;
• Good quality sleep;
• No body pain occurring at the same time.

An individual’s commitment and motivation to withdraw also influences the likelihood of success. Take the time to thoroughly discuss the process of withdrawal and understand the reasons why it is needed, as you are more likely to withdraw successfully if you do. You are likely to require support during withdrawal. Be sure to discuss individuals and organisations which can support you through withdrawal so that you are well prepared.
Withdrawal is less likely to be successful if you have psychological drug dependence. If this is the case the doctor may refer you for cognitive behavioural therapy to assist with your withdrawal attempt.

How is chronic daily headache treated?

Chronic daily headache is treated differently depending on whether or not the condition occurs as a result of medication overuse, as medication overusers typically fail to respond to medicines used to treat migraine.

Chronic migraine without medication overuse

The majority of individuals who experience chronic migraine (found to be 70% in one study) use medicines to treat acute headache episodes. Treatment of acute episodes of chronic migraine involves the use of similar agents used in episodic migraine treatment. They include:

• Simple analgesics;
• Non-steroidal anti-inflammatory drugs (NSAIDs);
• Opioids;
• Triptans, a class of drugs which act as serotonin agonists which are usually only used if simple analgesics and NSAIDs fail to achieve pain relief;
• Ergotamines, a class of drug used in the treatment of migraine for over 5 decades, which has largely been replaces by triptans.

There is considerable debate regarding when medication for acute attacks should be taken. Early treatment reduces the severity of attacks and is thought to also reduce the frequency of attacks, thus facilitating reduced medication use. However, some argue that taking medication early in the course of a headache, before severe symptoms arise may encourage overuse of medicine. Discuss the best time to take preventative medications with your doctor and always use medicines according to your doctor’s advice.

Medication overuse headache

The aim of treatment is to reduce headache frequency and severity, but also to reduce the quantity of medication used and increase the efficacy of medication when it is used. Treatment success is defined as a reduction in headache days ?50% within 6 months.
Use of alternative medications is often complicated as the response of an individual with medication overuse headache to alternate drugs is also blunted, often making alternative medications of limited or no use. In the short term, administering another dose of the offending medication relieves headache symptoms but also perpetuates the cycle of medication overuse and headache. To break the cycle, medication overuse must be managed prior to instituting other pharmaceutical treatments for medication overuse headaches.

Withdrawal of overused medication

Withdrawal of the overused medication is the first step in treating individuals with medication overuse headache. Alternate medications become effective once the withdrawal effect has resolved; however, in the immediate term withdrawing individuals will experience withdrawal symptoms which must be managed. Take time to discuss with the doctor why withdrawal of the drug is necessary to improve headache symptoms, and be sure you have information about the short term worsening of symptoms which occurs during withdrawal, so you know what to expect. The timing of withdrawal should be planned to limit disruption to your life, for example you may need to arrange leave from work or a carer for your children.
Abrupt withdrawal of the implicated medication is recommended. Gradual withdrawal is usually ineffective; however, it may be appropriate in some cases. Always follow your doctor’s advice. They may recommend or prescribe another medication (e.g. an NSAID) to help you cope with the symptoms of withdrawal. They may recommend you be admitted to hospital whilst undergoing withdrawal and withdrawal in this setting is more likely to be successful. However, some individuals can go through withdrawal at home. Whatever the case it is important to drink plenty of fluid to maintain proper hydration.
Symptoms including nausea, vomiting and sleep disturbances are common and should be expected. The duration of withdrawal symptoms varies between individuals and depending on the offending medication (Table 1). In cases where triptans are overused, withdrawal symptoms are typically of a shorter duration than with other types of medicine.
Table 1: Duration of withdrawal symptoms with various medications

Medicine	Duration of withdrawal headache	Duration of withdrawal symptoms	Time from withdrawal to overall improvement
Triptans	4.1 days	1 day	7–10 days
Ergots	6.7 days	2.5 days	–
Analgesics	9.5 days	2.2 days	2–3 weeks
Opioids	–	–	2–4 weeks

Managing withdrawal symptoms

Withdrawal symptoms such as vomiting and sleep disturbance may occur for 1–3 days following medication withdrawal and withdrawal headaches may persist for up to 10 days. During the withdrawal phase the doctor may prescribe another medicine to reduce withdrawal symptoms. Sometimes you will also be prescribed a gastro-protective agent (to reduce gastro-intestinal disturbances) or an antiemetic (to reduce nausea and vomiting).

Reviewing primary headache condition

Following withdrawal you should return to your doctor after 2–3 weeks, so that your headaches and response to withdrawal can be reviewed. Full recovery may take several months and most people revert to experiencing their former headache type following withdrawal (e.g. someone whose migraine headaches transformed to chronic migraine will likely revert to episodic migraine). At this time the previously overused medicine may need to be reintroduced. Be aware that medication overuse can re-occur. Follow the doctor’s instructions carefully and avoid using the medicine more often than prescribed.

Preventing relapse

Relapse is defined as using headache medications on >15 days per month for at least 3 months following successful withdrawal. It typically occurs within a year withdrawal. For example, in one study 41% of individuals had relapsed within a year of withdrawal, increasing to 45% at 4 years post-withdrawal. People who are more likely to relapse include those who:

• Experience tension-type headaches or combined tension and migraine type headaches;
• Experience frequent migraines (>8 days per month) of long duration;
• Have poor improvement following withdrawal;
• Have tried a greater number of preventative treatments;
• Are male;
• Used combined analgesics containing codeine or caffeine.

If you meet any of the above criteria, you have an increased risk of relapsing to medication overuse. Discuss strategies to prevent this (including regular monitoring and support) with your doctor and ensure you are well informed regarding the potential for relapse. Combined analgesics (e.g. those containing caffeine) should not be used; ideally the primary headache syndrome should be managed with non-pharmaceutical interventions which may include acupuncture, massage and behavioural therapies. Prophylactic medications may be instituted to avoid the need for acute medication.

Referral

Individuals who have developed psychological medication dependence may require referral for cognitive behavioural therapy. Those with comorbid psychological disorders (e.g. depression) require treatment for these comorbidities and may need to see a psychiatrist. If you successfully withdraw from using offending medications but do not experience improvement in your headache symptoms, you also require diagnostic review and will probably be referred to a specialist. You may be referred to a neurologist if your withdrawal attempt is unsuccessful.

Chronic daily headache prevention

Prophylactic treatment of chronic migraine

Prophylactic treatment, that is the use of preventative medications for chronic migraine (without medication overuse) aims to reduce the frequency of acute attacks, lessen the impairment the individuals experience during an attack and reduce the use of acute medication. Most of the medications used in migraine prophylaxis (e.g. ?-blockers, anticonvulsants, and tricyclic antidepressants) have not been evaluated for efficacy in treating chronic migraine, however they are commonly used and considered effective in clinical practice.

Topiramate

Topiramate (for example, sold as Topamax) is an anti-seizure medication, also used in the treatment of migraine. It is the medicine with the best evidence for effectiveness in preventing chronic migraine. Using this medicine has been shown to reduce the frequency of chronic migraine, however it is not known whether or not individuals who use topiramate also reduce the quantity of medicine used to treat acute migraine attacks.

Gabapentin

Gabapentin (for example, sold as Pendine and Gabahexal) is another anti-seizure medicine which has been demonstrated effective in reducing the frequency of chronic migraine. It has also been shown to reduce migraine-associated disability.

Tizanidine

Tizanidine is a muscle-relaxing medicine which has proven effective in reducing the average number of headache days for individuals who experience chronic migraine, as well as reducing the intensity and duration of headaches when they do occur.

Sodium valproate

Sodium valproate, (for example sold as Valpro and Epilim) a sodium-blocking medication commonly used as anti-seizure treatment has been shown to reduce the frequency and severity of chronic migraine pain.

Botulinum toxin A

Botulinum toxin A has demonstrated efficacy in the prophylactic treatment of chronic migraine. In one study, individuals who received botulinum toxin A injections experienced significantly less frequent headaches compared to those receiving placebo injection. However, the reduced frequency of headache did not result in a similar reduction in use of acute medications.

Medication overuse headache

Preventing medication overuse is the primary measure for preventing medication overuse headache, the most common type of daily headache. Be sure to obtain advice from your doctor regarding the dangers of medication overuse and the potential for chronic migraine to develop. Monitor your headaches and medication use by recording these in a diary, so you have an accurate record of how much medication you use.
In Australia, codeine preparations are most commonly implicated in medication overuse headaches, so monitoring medication use is particularly important if your medicine contains codeine. Preparations with up to 12.5 mg of codeine are available over the counter at pharmacies and up to 30 mg per tablet preparations may be prescribed for headache. If you are using a codeine-containing medicine and notice it is becoming less effective, talk to your doctor. Do not increase the dose or change medicines without medical advice and avoid opioid containing medications unless advised by your doctor to use these.
Codeine and opioid withdrawal is particularly challenging. Triptans and ergotamine are also commonly involved in medication overuse headaches. In order to prevent medication overuse, these medications should be used infrequently, if at all. The following maximum doses are recommended:

• Triptans – 1–2 doses per week;
• Codeine – once a month or preferably not at all;
• Ergot alkaloids – never;
• Injected narcotics – once every 2 months.

Medications containing caffeine, opioids or tranquilisers should be avoided. Early prophylaxis, which may involve medication, behavioural or natural therapy components, should be instituted to reduce the number of acute attacks requiring medication and reduce overall medication use. Note that medication overusers typically fail to respond adequately to pharmaceutical prophylaxis and withdrawal of overused medications must usually precede preventative pharmacotherapy. If you have previously trialled and failed to respond to one or more prophylactic medicines, you require withdrawal treatment. If you have not previously trialled a prophylactic medicine, you will probably be prescribed a trial of prophylactic medicine before a withdrawal attempt is made.
 
Article kindly reviewed by:
Associate Professor Karl Ng MB BS (Hons I) FRCP FRACP PhD CCT Clinical Neurophysiology (UK) Consultant Neurologist – Sydney North Neurology and Neurophysiology (download referral form and map); Conjoint Associate Professor – Sydney Medical School, University of Sydney; and Editorial Advisory Board Member of the Virtual Neuro Centre.
 

Headache Australia is the only Australian charity that aims to support the more than 5 million Australians affected by headache and migraine. Headache Australia is an initiative of the Brain Foundation – a national charity raising funds for research from community donations.

For more information, see Headache Australia.

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