Causes of migraine

The brain contains a natural chemical called serotonin. When a migraine happens, something triggers a drop in serotonin levels. This causes an area of the brain to send messages to a nerve in the face and to blood vessels in the head. The blood vessels widen, and it's this that causes pain. The serotonin drop also affects the way other parts of the brain work, which can result in other symptoms that some people experience as an "aura".

In women who suffer from migraines, hormone changes may also be involved. In some women, migraines occur a few days before, during, and immediately after a period. About 70% of women who have migraines can relate their migraine headaches to their menstrual period.

About 80% of people who get migraine headaches have a family history of migraines, which suggests that there may be a genetic basis to migraines.

Some people find that their migraines are triggered by something. Triggers might include:

  • certain foods – such as chocolate, cheese, red wine, citrus
  • fruits, coffee, tea, tomatoes, potatoes
  • too much or too little sleep
  • changes in hormone balance in women – such as periods, the pill, menopause
  • stress or even relaxation
  • irregular meals
  • caffeine withdrawal
  • physical activity
  • smoking
  • flashing lights
  • noise
  • weather – high pressure conditions, changes in pressure, hot dry winds, seasonal changes, exposure to sun and glare
  • exercise – too much or too little
  • sexual arousal
  • smells – paint, fumes from car heaters or perfume

Often, several triggers work together to provoke a migraine. Unfortunately, avoiding triggers may not prevent migraines, as most migraines are not caused by a single, identifiable trigger.

Types of migraine

There are two main types of migraine – common and classic.


Classic migraine - migraine with aura. This affects about a quarter of all migraine sufferers. People sense when a migraine is coming on. Nervous system symptoms – called an aura – develop before the migraine symptoms. These may include:

  • yawning
  • hunger and thirst
  • visual disturbances – such as seeing flashing lights or zig-zag lines

Occasionally, the symptoms can be more severe – there may be a tingling around the mouth or in one arm, difficulty in speaking, or weakness in an arm or leg. Aura symptoms usually settle down within an hour. Some people get the aura without the subsequent headache. This is more common in older people.

Common migraine - Around three quarters of people who get migraines are affected by common migraine. The headache comes on quite suddenly, without any warning at all. There are the usual migraine symptoms – headache, sickness, sensitivity to light, but there are no aura symptoms.

Symptoms of migraine

A severe migraine attack can cause a persistent throbbing or pounding pain, with sensitivity to light, sound and movement. The pain may be just on one side of the head, though there may be pressure on both. Attacks can last for up to 72 hours. There may also be nausea, be sickness or diarrhea, and a feeling of exhaustion.

Diagnosis of migraine

It is possible that migraine symptoms are caused by something more serious. So, always see a doctor if you experience any of the following:

  • aura symptoms that are always on the same side of the body, or last less than five minutes or more than an hour
  • aura symptoms without a headache
  • a sudden change in the character of your migraine – attacks coming more often, for instance, or treatment not helping
  • headache after you exercise
  • your first ever attack when you’re over 50
  • stomach pains
  • nervous system problems – difficulty in walking, or disturbance of vision between attacks
  • a high temperature
Treatment of migraine

(I) Over-the-counter medicines

Mild migraine attacks settle in a few hours. It’s best to rest in a quiet, darkened room, and take simple painkillers, such as paracetamol, aspirin or ibuprofen. Preparations containing the anti-sickness drug buclizine may help with any nausea and sickness.

(II) Prescription medicines

There are many prescription drugs available if these simple remedies don’t help. Drugs called metoclopramide and domperidone can stop nausea and vomiting. A combination of aspirin and metoclopramide is also now available, to help with pain and nausea. And the findings of a drug in trial called tolfenamic acid suggest that it is effective.

The triptan group of drugs work by correcting the serotonin imbalance. These are available as tablets, injections, nasal sprays or dissolvable wafers. But they should not be used after a heart attack or stroke, or in people who suffer from high blood pressure. Some people get side-effects from these drugs, such as dizziness, a feeling of pressure in the neck or chest area, nausea and vomiting.

Prevention of migraine

If avoiding triggers doesn’t seem to help, and you get at least two severe migraines a month, you might want to consider taking daily preventive treatment. These include:

  • a-blockers, such as propranolol
  • tricyclic antidepressants, such as amitriptyline
  • pizotifen

The anti-epileptic drug sodium valproate may also be effective, but is not a common treatments due to the side-effects. Another option is the drug methysergide, but this can have dangerous side-effects and should only be administered under hospital supervision. For menstrual migraine, hormone treatment with oestrogen may help.

Whatever the approach, it will take some time, and support from a doctor, for each individual to find a treatment that best helps manage their migraine.

Last Updated: Aug 2017
Please note that all medical health articles featured on our website have been reviewed by Quality Healthcare doctors. The articles are for general information only and are not medical opinions nor should the contents be used to replace the need for personal consultation with a qualified health professional on the reader’s medical condition.