Trigeminal Autonomic Cephalalgias (TACs) – Paroxysmal Hemicrania

Paroxysmal hemicrania (PH) is a rare primary headachedisorder that belongs to a group of related conditions called trigeminal autonomic cephalalgias. These headachesyndromes share lateralized clinical features, relatively short-lasting attacks, and prominent cranial parasympathetic autonomic features as their key phenotype. According to the current International Classificationof Headache Disorders(ICHD-II), this group includes cluster headache, PH, and short-lasting unilateral neuralgiform headachewith conjunctival injectionand tearing.