Migraine is a type of recurring headache. It involves nerves and brain chemicals. Other sensations, such as auras, may come before a migraine headache.

There are 2 types of migraines:

  • Occurring with an aura—formerly called a classic migraine
  • Occurring without an aura—formerly called a common migraine

Migraine may happen several times a week or once every couple of years. They can be so severe that they interfere with the ability to work and carry on normal activities.

While the precise cause is not known, many potential triggers have been identified. Common triggers include:

  • Environmental triggers, such as odors and bright lights
  • Dietary triggers, such as alcohol
  • Certain medications
  • Changes in sleep patterns
  • Stress
  • Physiologic changes, such as menstruation and puberty
  • Weather changes

A trigger sets the process in motion. It is possible that the nervous system reacts to the trigger by conducting electrical activity. This spreads across the brain. It leads to the release of brain chemicals, which help regulate pain.