SUNCT syndrome: an update.

SUNCT (Shortlasting Unilateral Neuralgiform Headache attacks with Conjunctival injection and Tearing) is a syndrome characterised by shortlived (5-240 s), strictly unilateral, orbital/periorbital, moderate-to-severe pain attacks, accompanied by rapidly developing conjunctival injection and lacrimation. Most attacks are triggered by mechanical stimuli, but there are also spontaneous attacks. Symptomatic periods alternate with remissions in an unpredictable fashion. In active periods, the attacks predominate during daytime, with a frequency that ranges from < 1 attack/day to > 30 attacks/h SUNCT is mainly a primary disorder, but is sometimes associated with intracranial structural lesions (symptomatic SUNCT). SUNCT has been included in the group of trigeminal autonomic cephalalgias, which are thought to depend on the activation of the trigeminal system together with the disinhibition of a trigeminofacial autonomic reflex. According to a few reports, SUNCT patients may benefit from carbamazepine, lamotrigine, gabapentin, topiramate or various surgical procedures. However, well-designed clinical trials are required before these therapeutic options can be sufficiently validated.