Migraines affect an estimated 28 million Americans. There are perhaps even more people with migraines who go undiagnosed. These headaches are characterized by intense pain that is felt on one or both sides of the head, around the temples, or behind one eye or ear. The pain, which is severe, can last a few hours or as long as two days. The exact causes of migraines are unknown, but common triggers may include lack of sleep, light, and certain foods. Some treatment options for migraines include medications, lifestyle changes, and alternative therapies (such as biofeedback).