A migraine is a severe, debilitating form of headache that typically appears as a throbbing ache near the side of the forehead. Over time, the ache often intensifies to a disabling pain. Migraines are usually a chronic condition, occurring repeatedly throughout a person’s life.

Migraines are considered a type of vascular headache because they involve blood vessels, nerves and chemicals in the brain. Although the exact cause of this type of headache is not fully understood, a number of factors that can trigger the condition have been identified. These include sensory stimulus (e.g., bright lights, loud noises, certain odors), stress and certain foods, such as chocolate or nuts.

A migraine differs from other types of headaches because it is usually more severe and often accompanied by a number of other symptoms, such as nausea or vomiting. In some people, temporary visual changes such as hallucinations or blind spots may occur before the headache appears. Known as aura, these warning symptoms occur in only about one–fifth of migraine suffers. Migraine with aura (classic migraine) and migraine without aura (common migraine) are the two most common types of migraine.

A number of serious conditions, including stroke, blood clot, and brain tumor, can cause severe headaches that may be mistaken for migraines. To rule out these conditions, a physician evaluates the patient by taking a medical history and performing a physical examination. Diagnostic tests such as MRI, CAT scan or electroencephalogram (EEG) may also be performed.

There is no known cure for migraines. However, there are a number of methods used to control symptoms and prevent future episodes. These include headache medications, biofeedback and self–hypnosis. Patients may help prevent migraines by avoiding factors that trigger the headaches.  

The National Headache Foundation (NHF) estimates that more than 28 million Americans experience migraine. The disease is more common in women, people between the ages of 15 and 55, and those with a family history of the condition.

People with other conditions are sometimes incorrectly diagnosed with migraines, but because symptoms and onset vary, some migraine sufferers go undiagnosed. The NHF estimates that even among people with complaints of severe disability from the condition, a large percentage do not receive a diagnosis of migraine.

Although they can be debilitating, migraines pose little risk of severe damage to a person’s overall health. However, patients should seek emergency medical treatment when a headache is accompanied by a symptom not experienced with previous migraines, such as speech problems or a loss of balance, as it may indicate a more serious medical condition.