what causes migraines

Migraines can be caused by a variety of factors, and the exact cause is not fully understood. However, genetics and environmental factors appear to play a role. Changes in the brainstem and its interactions with the trigeminal nerve, as well as imbalances in brain chemicals such as serotonin and calcitonin gene-related peptide (CGRP), might be involved. Migraine triggers can include hormonal changes, certain medications, alcohol, caffeine, stress, sensory stimuli, sleep changes, and certain foods. Other possible triggers include loud noises, bright lights, and strong smells