Allodynia and migraine.

An impaired processing of sensory afferents in the brainstem plays a key role in the development of migraine attack and for many of its clinical aspects. The repetition or prolonged of painful stimuli over time would be able to produce a prolonged and reversible increase of excitability and synaptic efficacy in the nociceptive pathways of the central nervous system. This phenomenon, known as sensitization, involves specifically the caudal trigeminal nucleus. Being an aspect of untreated migraine, allodynia is more common in patients with chronic migraine and migraine with aura, often associated with motor and sensory symptoms sometimes present during the attacks. The presence of allodynia in the course of migraine attack greatly increases the disability of the patient and its recognition, as well as from a therapeutic point of view, it is essential in the management of migraine patients.