Migraine characteristics can include:

• Pain typically on one side of the head
• Pain has a pulsating or throbbing quality
• Moderate to intense pain affecting daily activities
• Nausea or vomiting
• Sensitivity to light or sound
• Attacks last four to 72 hours, sometimes longer
• Visual disturbances or aura
• Exertion such as climbing stairs makes headache worse

Many factors can trigger migraine attacks, such as alteration of sleep-wake cycle; missing or delaying a meal; medications that cause a swelling of the blood vessels; daily or near daily use of medications designed for relieving headache attacks; bright lights, sunlight, fluorescent lights, TV and movie viewing; certain foods; and excessive noise. Stress and/or underlying depression are important trigger factors that can be diagnosed and treated adequately.

• Hormonal changes in women. Fluctuations in estrogen seem to trigger headaches in many women with known migraines. Women with a history of migraines often report headaches immediately before or during their periods, when they have a major drop in estrogen. Others have an increased tendency to develop migraines during pregnancy or menopause. Hormonal medications — such as oral contraceptives and hormone replacement therapy — also may worsen migraines, though some women find it's beneficial to take them.
• Foods. Some migraines appear to be triggered by certain foods. Common offenders include alcohol, especially beer and red wine; aged cheeses; chocolate; aspartame; overuse of caffeine; monosodium glutamate — a key ingredient in some Asian foods; salty foods; and processed foods. Skipping meals or fasting also can trigger migraines.
• Stress. Stress at work or home can instigate migraines.
• Sensory stimuli. Bright lights and sun glare can produce migraines, as can loud sounds. Unusual smells — including pleasant scents, such as perfume, and unpleasant odors, such as paint thinner and secondhand smoke, can also trigger migraines.
• Changes in wake-sleep pattern. Either missing sleep or getting too much sleep may serve as a trigger for migraine attacks in some individuals, 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. Certain medications can aggravate migraines.