Migraine is a debilitating, neurological condition, characterised by recurrent headache attacks and a range of non-headache symptoms including nausea, vomiting, and heightened sensitivity to light, smells and noise.
Migraine attacks can start in childhood and are thought to affect one in seven people (around one in every five women and around one in every 15 men).1 It has been estimated that there are over 190,000 migraine attacks every day in the UK.
Adults with migraine report episodic attacks with specific features – head pain and nausea are the most characteristic. A typical attack has well defined stages that help differentiate migraine from other headaches. Not all stages may be experienced during an attack and only 10-30 per cent of sufferers ever experience aura. Each stage can vary in length and severity:
- Prodrome – a ‘warning’ period, up to 24 hours before onset of headache, involving specific signs (e.g. tiredness, mood change, craving sweet foods, thirst)
- Aura – usually starts before the headache, developing gradually, lasting up to 60 minutes. Typical symptoms experienced include visual disturbances (e.g. blind/coloured spots, flashing lights, zig-zag lines); sensory/motor problems (e.g. numbness, tingling, weakness, dizziness) and speech disturbance (e.g. mixing up words)
- Migraine headache/main attack – in those who experience aura, headache can begin during aura, or follows within 60 minutes
- Resolution/recovery – migraine resolves gradually, often following sleep. Sufferers
can feel drained for up to two days after an attack.
Patients are described as chronic migraine or episodic migraine sufferers, depending on the frequency and intensity of attacks:2
- Episodic migraine is defined as headache which occurs on fewer than 15 days a month and can be further subdivided into low frequency (one to nine days per month) and high frequency (10-14 days per month). Those with episodic migraine typically lose four to eight days per month to the condition
- Chronic migraine is defined as headache which occurs on at least 15 days a month and has the characteristics of a migraine headache on at least eight days a month for more than three months.
It is an unfortunate fact that a substantial amount of a migraine sufferer’s daily life will be lost to ill health in their most productive years (between 25-55 years old).3
Migraine attacks can often cause debilitating throbbing, which can be described as pounding, banging or pulsing in the head.
During a migraine attack, gastric stasis can occur that can lead to nausea or even vomiting. The absorption of painkillers is also affected, which may reduce their effectiveness
Fatigue is a common symptom of migraine with many people feeling extremely tired before and after attacks, suffering with low energy and frequently yawning
Aura usually consists of visual disturbances, such as zigzags, flashes of different colours and light, blind spots, or even other disturbances, such as odd smells, tingling on one side of the face or in an arm or leg, and difficulty speaking
Migraine is three times more common in women than in men. Hormonal changes, especially fluctuations in oestrogen before or during menstrual periods, in pregnancy and in the perimenopause, are known to be a trigger for migraine attacks in many women
Many people with migraine often feel irritable or depressed, before, during or after migraine attacks. Anxiety about getting an attack is very common
Dizziness may be part of an aura but may also occur in a type of migraine called vestibular migraine, where headache is less of a feature
Some people with migraine experience true weakness on one side of the body (known as hemiplegic migraine) or a sensation of weakness.
Lifestyle factors and mood symptoms that contribute to migraine frequency/severity
- Sleep patterns: insomnia, obstructive sleep apnoea
- Skipping meals and fluids
- Exercise frequency
- Analgesic/medication overuse
- Caffeine use
- Depression screening.
A diagnosis of migraine is largely dependent on a neurological assessment, a thorough evaluation of an individual’s medical history, and ruling out other diagnoses. For a comprehensive diagnosis, information should include a history of headaches in the family, the clear features of the presenting headaches, and the impact that the headaches have on the patient’s ability to engage in or perform daily activities.
Pharmacists are in a prime position to help patients who are undiagnosed, recently diagnosed or who may be visiting the pharmacy regularly for OTC painkillers by discussing their headache history, the type of pain experienced, as well as the duration, frequency, intensity and symptoms.
Patients should be encouraged to keep a migraine or headache diary. This should record useful information on the effectiveness of treatments, how much sleep they get, daily activities, what they eat and drink, exercise taken, mood, menstrual cycle, when a migraine starts and what medication they took.
A high proportion of patients self-medicate successfully with OTC products. Symptomatic treatment with simple oral analgesics is a sensible first step. Oral analgesics are best taken early in an attack because gastric stasis develops as a migraine progresses, and drug absorption can be impeded as a result. Analgesic absorption can be optimised by use of a soluble formulation.
If nausea and vomiting are troublesome, an oral anti-emetic could be tried. Options include domperidone and metoclopramide at a maximum daily dose of 30mg.
If simple analgesics prove ineffective, triptans become the next drug of choice (e.g. sumatriptan, rizatriptan, naratriptan). Triptans act at 5-HT1 receptors on cranial nerves and blood vessels to relieve pain and associated migraine symptoms.
Common side-effects with triptans include nausea; jaw, neck or chest tightness, pressure or squeezing; rapid heart rate; fatigue; numbness or tingling (especially involving the face); or a burning sensation over the skin. A triptan is usually tried for three separate attacks before deciding whether it is suitable.
Medicines that have been used as prophylactics include angiotensin II blockers (e.g. candesartan), and the anticonvulsants topiramate and sodium valproate. The latter can cause neuro-developmental disability in unborn babies, so girls and women of childbearing potential should only take if prescribed and supervised by a specialist, and when other medications have not been tolerated or have been found to be ineffective.
Botox is also approved for use on the NHS for the treatment of chronic migraine in adults after it was discovered to be effective for people with chronic migraine while being used for cosmetics treatment. Botox is recommended for people with chronic migraine who:
- Have failed on at least three preventive treatments
- Have been appropriately managed for medication overuse headache.
“Oral analgesics are best taken early in an attack because gastric stasis develops as a migraine progresses impeding drug absorption”
|Table 1: Classification of headache disorders|
|Chronic migraine diagnostic criteria||
Headache occurring on ≥15 days/month for >3 months which, on ≥8 days/month, has the features of migraine headache
A: Headache (migraine-like or tension-type like) on ≥15 days/month for >3 months and
B: Occurring in a patient who has had at least five attacks fulfilling criteria B-D for migraine without aura and/or criteria B and C for migraine with aura
C: On ≥8 days/months for >3 months, fulfilling any of the following:
D: Not better accounted for by another ICHD-3 diagnosis
|Migraine without aura diagnostic criteria||
Recurrent headache disorder manifesting in attacks lasting 4-72 hours. Typical characteristics of the headache are unilateral location, pulsating quality, moderate or severe intensity, aggravation by routine physical activity, and association with nausea and/or photophobia and phonophobia
A: At least five attacks fulfilling criteria B-D
B: Headache attacks lasting 4-72 hours (untreated or unsuccessfully treated)
C: Headache has at least two of the following four characteristics:
D: During headache, at least one of the following:
E: Not better accounted for by another ICHD-3 diagnosis
|Migraine with aura diagnostic criteria||
Recurrent attacks, lasting minutes, of unilateral fully reversible visual, sensory or other central nervous system symptoms that usually develop gradually and are then often followed by headache and associated migraine symptoms
A: At least two attacks fulfilling criteria B and C
B: One or more of the following fully reversible aura symptoms:
C: At least three of the following six characteristics:
D: Not better accounted for by another ICHD-3 diagnosis
|Medication overuse headache diagnostic criteria||
Headache occurring on ≥15 days/month in a patient with a pre-existing primary headache and developing as a consequence of regular overuse of acute or symptomatic headache medication (on ≥10 or ≥15 days/month, depending on the medication) for >3 months. It usually, but not invariably, resolves after the overuse is stopped
A: Headache occurring on ≥15 days/month in a patient with a pre-existing headache disorder
B: Regular overuse for >3 months of one or more drugs that can be taken for acute and/or symptomatic treatment of headache
C: Not better accounted for by another ICHD-3 diagnosis
Calcitonin gene-related peptide (CGRP) monoclonal antibodies (MAbs) are described by Migraine UK as “the first preventive medicines specifically developed for migraine treatment”.
During a migraine attack some primary sensory neurones – including branches of the trigeminal nerve – release CGRP which, in turn, dilates arterioles (small arteries) and triggers allodynia (heightened sensitivity to touch). Indeed, numerous stimuli that trigger or exacerbate migraine evoke CGRP release and levels in cranial blood vessels rise during an attack.
Monoclonal antibodies targeting CGRP (fremanezumab and galcanezumab) or its receptor (erenumab) are approved for episodic (fewer than 15 days of attacks a month) and chronic (at least 15 days) migraine4 but must be prescribed by a specialist.
Until now CGRPs have only been available as monthly and quarterly injections but, at the end of May, NICE issued final draft guidance recommending rimegepant (Vydura from Pfizer) as an option for preventing episodic migraine in adults where at least three previous preventive treatments have failed.
“Rimegepant is the first oral treatment for migraine to be recommended by NICE and for many thousands of people it is likely to be a welcome and more convenient addition to existing options for a condition that is often overlooked and undertreated,” says Helen Knight, director of medicines evaluation at NICE. Rimegepant is taken every other day as a wafer that dissolves under the tongue. NICE estimates that the launch will benefit 145,000 people who suffer from episodic migraine.
Migraine UK has expressed its disappointment that rimegepant had not been approved for acute treatment. “Too many people with migraine end up with medication overuse headache as a result of their migraine treatment, which has a serious impact on their lives,” says chief executive Rob Music. “This is an impact which is preventable if migraine is treated effectively.
“Gepants can help prevent this happening. While we welcome that [rimegepant] has been approved for the preventive treatment of migraine, we are very disappointed by the decision not to approve it for acute treatment.”
The Scottish Medicines Consortium (SMC) has approved rimegepant for acute treatment. Both NICE and SMC are currently reviewing another gepant, atogepant, and NICE has said that the appraisal will be discussed at a further committee meeting in August, when the final guidance on rimegepant is also expected. The Migraine Trust hopes that this will lead to approval of the drug for the acute treatment of migraine, particularly in light of the SMC’s decision.
Pharmacists can play an important role in the prevention and management of migraine by educating patients on the benefits of preventive medications, providing realistic expectations of treatment outcomes, and identifying migraineurs who may benefit from further assessment.
- NHS 111 Wales – Migraine
- National Institute for Health and Care Excellence – migraine
- TheraSpecs - Migraine through the Years: Migraines in Adulthood and Middle Age
- Neuroscience Letters 2022; 768:136380.