serotonin is a chemical messenger called a neurotransmitter and is involved in communicating the message to the brain to expand (dilate) or close (constrict) the blood vessels. when these blood vessels dilate and constrict they stimulate nerves that carry pain-producing messages in the brain leading to headache pain particularly the pain of migraine. serotonin is also responsible for controlling mood attention sleep and pain.
what is serotonin related to migraines?