Food additives. The sweetener aspartame and the preservative monosodium glutamate, found in many foods, may trigger migraines.
Drinks. Alcohol, especially wine, and highly caffeinated beverages may trigger migraines.
Stress. Stress at work or home can cause migraines.
Sensory stimuli. Bright lights and sun glare can induce migraines, as can loud sounds. Unusual smells — including perfume, paint thinner, secondhand smoke and others — can trigger migraines in some people.
Changes in wake-sleep pattern. Missing sleep or getting too much sleep may trigger migraines in some people, as can jet lag.
Physical factors. Intense physical exertion, including sexual activity, may provoke migraines.
Changes in the environment. A change of weather or barometric pressure can prompt a migraine.
Medications. Oral contraceptives and vasodilators, such as nitroglycerin, can aggravate migraines.