A migraine produces a host of changes in vascular tone in blood vessels that are in the brain. The end result of vasodilation of these vessels is a stimulation of central reflexes that stimulate the vagus nerve. This nerve in turn stimulates the stomach and has important nervous effects on the heart. The end result--vasodilation (low BP), along with nausea and a slow heart rate-a vasovagal event.
POSTED BY: STEVEN AJLUNI, MD