Migraine Headaches

What is a migraine headache?

This often severe, throbbing type of headache is different from other types of headaches in that symptoms other than pain occur with the headache. Nausea and vomiting, lightheadedness, sensitivity to light (photophobia), and other visual disturbances are common migraine symptoms. A migraine headache may last from 4 to 72 hours.

Migraines are also unique in that they have distinct phases. Not all people have each phase, however. The phases of a migraine headache may include:

  • Premonition phase. A change in mood or behavior that may occur hours or days before the headache.
  • Aura phase. About one-third of people who have migraine headaches describe having an unusual “feeling” or aura before the headache. The aura phase includes visual, sensory, or motor symptoms that occur just before the headache. Examples include hallucinations, numbness, changes in speech, visual changes, and muscle weakness. Migraine sufferers may or may not have an aura before the beginning of the headache.


  • Headache phase. This is the period during the actual headache. Throbbing pain occurs on one or both sides of the head. Sensitivity to light and motion is common, as are depression, fatigue, and anxiety.
  • Headache resolution phase. Pain lessens during this phase, but may be replaced with fatigue, irritability, and trouble concentrating. Some people feel refreshed after an attack, while others do not.

Headaches are classified as with or without aura.

What causes migraine headaches?

Experts are not certain what causes a migraine headache. Many experts think an imbalance in brain chemicals, such as serotonin, and changes in nerve pathways are involved. Migraines may also run in families suggesting a genetic link.

What are the symptoms of migraine headaches?

To get an accurate diagnosis, it is important to describe your migraine symptoms to your doctor. Also, it is helpful to track when migraines occur (such as dates and times) and the details associated with migraine headaches. These are the most common symptoms of migraine headaches:

  • Throbbing, severe headache pain with a specific location either on one side or another
  • Nausea and vomiting, lightheadedness, sensitivity to light may also occur during a migraine
  • Visual disturbances, even lack of sight, may occur for a short period of time with a migraine headache
  • A change in mood or behavior that may occur hours or days before the headache
  • Depression, fatigue or anxiety may occur
  • As the headache resolves, you may notice fatigue, irritability, and trouble concentrating
  • Some headaches have an aura before a migraine, which may be experienced as a flashing light or other visual changes

The symptoms of migraine headache may look like other conditions or medical problems. Always see your healthcare provider for a diagnosis.

How are migraine headaches diagnosed?

Migraine headaches are diagnosed based on your symptoms and a physical exam. You may need other tests or procedures to rule out underlying diseases or conditions.

Tracking and sharing information about your headache with your doctor helps with the process of making an accurate diagnosis. Consider writing down the following information to take to your medical appointment:

  • Time of day when your headaches occur
  • Specific location of your headaches
  • How your headaches feel
  • How long your headaches last
  • Any changes in behavior or personality
  • Effect of changes in position or activities on the headache
  • Effect of headaches on sleep patterns
  • Information about stress in your life
  • Information about any head trauma, either recently or in the past

Diagnostic tests that may be used to confirm a migraine diagnosis include the following:

  • Blood tests. Various blood chemistry and other lab tests may be used to check for underlying conditions.
  • Sinus X-rays. An X-ray to evaluate for congestion or other problems related to the headaches.
  • MRI. A diagnostic procedure, usually of the head or neck, that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures
  • CT scan or computed tomography scan. A diagnostic imaging procedure that uses X-rays and computer technology to make horizontal, or axial, images (often called slices) of the body or head. CT scans show more detail than standard X-rays.
  • Spinal tap (also called a lumbar puncture). A special needle is placed into the lower back, into the spinal canal, which is the area around the spinal cord. The pressure in the spinal canal and brain can then be measured. A small amount of cerebral spinal fluid (CSF) can be removed and sent for testing to determine if there is an infection or other problems. CSF is the fluid that surrounds the brain and spinal cord.