A migraine is a severe, painful headache that is often preceded or accompanied by sensory warning signs such as flashes of light, blind spots, tingling in the arms and legs, nausea, vomiting, and increased sensitivity to light and sound. The excruciating pain that migraines bring can last for hours or even days.
Migraine headaches result from a combination of blood vessel enlargement and the release of chemicals from nerve fibers that coil around these blood vessels. During the headache, an artery enlarges that is located on the outside of the skull just under the skin of the temple (temporal artery). This causes a release of chemicals that cause inflammation, pain, and further enlargement of the artery.
Migraine headaches can be very debilitating. A migraine headache causes the sympathetic nervous system to respond with feelings of nausea, diarrhea, and vomiting. This response also delays the emptying of the stomach into the small intestine (affecting food absorption), decreases blood circulation (leading to cold hands and feet), and increases sensitivity to light and sound.