There are four phases of migraine: prodrome, aura, headache and postdrome. Not every person experiences every phase with every migraine.
Migraine is generally episodic, does not cause death and is not contagious. Consequently, migraine is the least publicly funded of all neurological illnesses relative to its economic impact.
Migraine affects some cross sections of the population more than others. In particular, migraine is three times more common in women than in men. Although migraine affects all ages, it usually begins in adolescence and is most disabling for individuals between 35 and 45 years — typically a highly productive period of life.
Migraine can be episodic, occurring only a few times a year, or chronic. In chronic migraine, headaches occur more than 15 days a month. Treatment of chronic migraine is problematic because when used more than a few days a week, acute therapies actually worsen the headaches in most people, underscoring the importance of effective prophylactic treatments that lower attack frequency.
More than one-third of people with migraine experience the aura — one or more transient sensory disturbances that may include geometric visual hallucinations, loss of vision, spreading numbness and tingling on one side of the body, language disturbance, and muscle weakness on one side of the body that ranges from mild clumsiness to paralysis.
Learn more about migraine and its diagnosis and treatment.