Migraines are painful, sometimes disabling headaches that are often accompanied by nausea, vomiting, and sensitivity to light, noise, and smell. These throbbing headaches usually occur on only one side of the head, although the pain can shift from one side of the head to the other or can occur on both sides at the same time.
Migraine headaches tend to recur. A migraine headache typically lasts 4 to 24 hours but in some cases can last up to 3 days. Some people have symptoms, such as visual disturbances, that occur before a headache starts. These symptoms are called a migraine aura.
Some people have several headaches per month. Others have headaches much less often. Treatment usually includes medicines to prevent a migraine from occurring or to stop a migraine after it begins. In some people, migraines may be triggered by certain foods or smells. No exposure to these triggers may stop the headaches.
WebMD Medical Reference from Healthwise