In contrast to tension headache, migraine is believed to result from pain which originatesfrom the blood vessels which run to supply the brain within the skull. The vessels arethought to constrict and then expand during a migraine attack, and this leads to the symptomof a throbbing headache. The one sided nature of the syndrome is attributed to the fact thatthis problem only affects the vessels on one side of the brain.
Migraine is distinguished from tension headache on the basis of some characteristicfeatures. In contrast to tension headache, many people report that a migraine attack mightcome on at a time when stress has been relieved, such as the weekend after a busy workingweek. Very often a dietary trigger can be found. Chocolate, coffee, cheese, monosodiumglutamate and red wine are amongst the most common dietary triggers for migraine. Theexperience of migraine often changes at puberty, during pregnancy or the menopause.Some people get better and some people get worse after these times of major hormonalchange.
The classical syndrome of migraine involves a period of a few minutes to hours of somewarning symptoms called an aura, although most (90%) of the patients with migraine do notexperience the aura. It is believed that the aura results from constriction of the blood vesselswhich supply a defined part of the brain. For this reason the symptoms of an aura can bevery like a stroke or TIA.
The most common form of aura which migraine patients experience involves visual disturbances, often including flashing lights or some loss of vision. Some have acharacteristic mood change, dizziness or a strange smell, and others may experience atemporary weakness of one half of the body (hemiparesis) or inability to speak (aphasia).
The migraine headache itself is characteristically one sided, often located behind or aboveone eye. In a severe case the patient may feel nauseated and may have diarrhoea orvomiting. Many people need to lie down in a darkened room. The headache usually lasts fora few hours. When it wears off some people report that they experience a period of a day orso of exhaustion, and some describe a lightened mood, sometimes described aseuphoria.
Some migraines are not so severe, and so in many cases it is difficult to distinguish themfrom tension headaches.
The treatment of migraine involves treatment to relieve the acute attack and treatmentaimed at prevention of future attacks.
Migraine will settle down without any treatment, but many people find that the pain andnausea is so debilitating that they seek medication. If migraine is relatively infrequent,painkillers are generally prescribed, although commonly much stronger preparations arerequired to have any effect on the pain of a bad migraine. Tablets which contain acombination of paracetamol with a morphine related drug such as dextropropoxyphene (Co-proxamol®) are commonly prescribed. Anti-nausea medication such as Maxolon®(metaclopramide) may also be prescribed for an acute migraine attack.
A relatively new preparation called sumatriptan (Imigran®) is available for very severesymptoms. This is available in a tablet and injection form, and is advised to be taken as earlyas possible to abort a migraine attack. This gives marked relief in over one third of patients,and so is commonly prescribed. This preparation reverses the dilation of the blood vessels inthe brain, but can have side effects resulting from constriction of other blood vessels in thebody. For example, angina is a known side effect. For this reason Imigran should not begiven to people with heart disease or hypertension.
To prevent further attacks it is helpful if the patient can determine whether there are anyavoidable triggers for the migraine. Keeping a headache diary can be useful in clarifying alink with dietary or other lifestyle factors. The offending trigger can then be avoided ifpossible.
All women with focal (classical) migraine should use alternative forms of contraception to theoral contraceptive pill, as the risk of stroke is increased in women with migraine who takethe pill.
There are a range of drug preparations which can be taken regularly to avoid migraine.Pizotifen (Sanomigran®) is the most commonly prescribed preparation. This has the sideeffect of drowsiness and weight gain, but will often reduce the frequency of attacks. Betablockers can also reduce the frequency of migraine. Propranolol is one of the mostcommonly prescribed beta blockers. Antidepressants such as amitryptiline can also helpreduce frequency of attacks.
In Chinese medicine the intensity and one sided frontal position of the typicalmigraine suggests that the pain is a manifestation of a mixed or full condition. LiverYang rising, Liver Fire Blazing and Stomach Heat might all give rise to the symptomsof migraine. A dislike of bright light suggests an imbalance of the Liver. Nausea,vomiting and diarrhoea can be attributed to Stagnant Liver Qi invading the Stomachand Spleen.
The fact that migraine is recurrent suggests that there is a longstanding tendency to imbalance of the Liver Official. Pent up emotions are likely to be a common underlying cause of Stagnation of Liver Qi. The underlying pathology of dilation of blood vesselssuggests that Heat is present, either as a result or as a cause of the Stagnation.
The simple pain-killers tend to move Blood and Qi. Imigran® causes constriction ofblood vessels. It therefore would appear to Clear Heat, but at the expense of causingmore Stagnation (constriction of blood vessels) of Blood and Qi. These preparationsare all suppressive in nature.
The drugs used to prevent migraine all have in common the tendency to induce Damp and Phlegm. They presumably work by literally damping down the pent up emotions so that they are not expressed in such a dramatic and uncomfortable way. These treatments are suppressive in nature.