Article topic: Hypnic Headache Authors: Wendy Saliba and Ali Hijazi Editors: Odette El Ghawi, Joseph Akiki Reviewer: Ethar Hazaimeh  Keywords: Hypnic headache, hypothalamus, ICDH-3, secondary causes, caffeine.  Abbreviations: Hypnic Headache (HH), International Classification of Headache Disorders, 2nd edition (ICHD-2), International Classification of Headache Disorders, 3rd edition (ICHD-3), Magnetic Resonance Imaging (MRI), non-steroidal anti-inflammatory drug (NSAID). Abstract  Background: Hypnic headache (HH), first reported by Raskin in 1998, is a rare primary headache disorder otherwise known as “alarm clock headache”. It is distinguished by headache attacks regularly developing and recurring during night sleep. Objective: This paper summarizes current knowledge on HH including […]