A migraine prodrome is a premonition or advance warning that a migraine is coming on. Prodromes can occur anywhere from a few minutes before the onset of a headache to days prior. While no one knows the specific cause of migraine prodromes, the prevailing theory is that they are part of neurochemical change in the brain that occurs before an attack. Approximately 60% of all migraineurs (people who have chronic migraines) experience some type of prodrome.
Migraine auras are a specific type of visual prodrome in which people see things that are not there, like flashes of light or haloes around object. This type of prodrome is rare and experienced by less than 25% of all migraineurs.
Many migraine sufferers describe mood alterations preceding an attack. Some people are euphoric, others fall into a profound despondence, and still others experience uncharacteristic irritability or impatience.
Some migraineurs describe their prodrome experience as an enormous spike in energy levels during the day preceding the headache itself. Others say that they know a migraine is coming because they get fatigued or listless or find themselves constantly yawning prior to onset.
Some migraine sufferers lose their appetite before a headache. Some sufferers find themselves ravenous the day or night before an attack. Still others have noticed that specific cravings tend to precede their migraine.
Insomnia is a frequent prodrome symptom for many migraineurs, as is difficulty falling asleep. Others experience lassitude and difficulty waking prior to a migraine.
Migraines are often difficult to diagnose and treat because no two migraine patients experience the same prodromes, if they experience one at all. Many migraineurs experience all of the prodrome symptoms at different times before a single headache, or different ones prior to different attacks.