Background: Cluster headache (CH), though not fully characterized until this century, is a relatively common primary headache disorder.
Methods: We reviewed pertinent literature on CH and related cephalalgias.
Results: We found that CH typically occurs in middle-aged men and has a characteristic cyclic temporal pattern. During the cluster cycle, CH paroxysms last from 15 to 180 minutes and are manifested by excruciating periorbital or upper facial pain. Associated autonomic symptoms such as lacrimation, rhinorrhea, conjunctival injection, and Horner's syndrome are common in CH. Its pathophysiology is not entirely understood, though it may include a complex cascade of autonomic, immunologic, and vascular phenomena.
Conclusions: Although its pathophysiology is still not completely understood, we present the most recent evidence regarding the underlying anatomic and biochemical basis for CH. We also present an update on the modern management of CH, including the appropriate use of standard and novel abortive and prophylactic agents, as well as more invasive treatment.