Headache at the emergency room: Etiologies, diagnostic usefulness of the ICHD 3 criteria, red and green flags

Introduction Non-traumatic headaches account for 0.5 to 4.5% at the emergency department (ED). Although primary headaches represent the most common causes, the likelihood of ominous etiology has to be considered by clinicians in order to avoid diagnostic and therapeutic pitfalls. Due to the absence...