This is a wakeup call: Alarm clock headache

Abstract

Hypnic headache, also known as alarm clock headache is one of the rare subtypes of primary headaches described in literature. It is a typical nocturnal headache which only occurs in sleep and generally affects elderly population. It needs to be differentiated from the other common primary headaches as the therapeutic options for it are very different from the other common headaches. The description is only through case reports and small case series. A review of this less known entity is discussed here.