Hypnic headache

Hypnic headache, also known as "alarm clock headache," is a rare primary headache disorder that exclusively occurs during sleep, typically awakening the affected individual at a consistent time each night. It predominantly affects individuals over the age of 50, though cases in younger adults have been reported. The condition is classified among other specified headache syndromes and is recognized by the International Classification of Headache Disorders (ICHD). The headache attacks are usually bilateral (though they can be unilateral), dull or throbbing in character, and last between 15 minutes and 4 hours after waking. Attacks occur at least 10 times per month, and often more than 15 times per month. Unlike cluster headaches, hypnic headaches are generally not accompanied by prominent autonomic features such as tearing or nasal congestion, although mild autonomic symptoms may occasionally be present. Some patients report associated nausea or photophobia, but these are typically less severe than in migraine. The disorder primarily affects the nervous system, specifically the central mechanisms regulating sleep-wake cycles and pain modulation, with hypothalamic dysfunction suspected as a contributing factor. The pathophysiology of hypnic headache remains incompletely understood, but disruption of circadian rhythm regulation and alterations in REM sleep architecture have been implicated. Treatment options include caffeine (taken as a cup of coffee before bedtime or caffeine tablets), lithium carbonate (which is considered one of the most effective preventive therapies), indomethacin, melatonin, and flunarizine. Caffeine is often tried first due to its favorable side-effect profile. There is no cure, but many patients achieve significant symptom reduction with appropriate preventive therapy. The condition tends to be chronic but may have periods of remission.

Inheritance

Sporadic

Usually appears on its own, not inherited from a parent

Age of Onset

Late onset

Begins later in life, typically after age 50

Source: openFDA + DailyMed · NDA / BLA labels with structured indications · refreshed weekly

Source: ClinicalTrials.gov · synced daily · phases, status, and PI names normalized at ingest

Source: NPI Registry + PubMed · trial PI roles cross-referenced with ClinicalTrials.gov · ranked by match score (publications + PI activity + community signal)

Source: NORD Rare Disease Centers + NIH Undiagnosed Diseases Network (UDN) · centers verified active within last 12 months

Source: PubMed + NIH RePORTER + openFDA + clinical-journal RSS · last 30 days · disease-tagged at ingest by AI extraction with human QC

Common questions about Hypnic headache