Hypnic headache

Hypnic headaches are benign primary headaches that affect the elderly, with the average age of onset being 63 +/- 11 years4. They are moderate, throbbing, bilateral or unilateral headaches that wake the sufferer from sleep once or multiple times a night. 1 They typically begin a few hours after sleep begins and can last from 15-180min. 2 There is normally no nausea, photophobia, phonophobia or autonomic symptoms associated with the headache. They commonly occur that the same time every night possibly linking the headaches with circadian rhythm, but polysomnography has recently revealed that the onset of hypnic headaches may be associated with REM sleep. 4
Lithium carbonate200-600mg at bedtime is an effect treatment for most patients but for those that can not tolerate Lithium, Verapamil, indomethicin or methylsergilide may be tried. Two patients have also responded to flunarizine 5mg. It has also been shown that 1-2 cups of coffee or 1-2mg of caffeine before bed can prevent hypnic headaches.

For diagnosis of hypnic headache syndrome, headaches should occur at least 15 times per month for at least one month. Included in the differential diagnosis of a new onset nighttime headaches in the elderly is drug withdrawal, temporal arteritis, Sleep apnea, oxygen desaturated, pheochomatoma, intracranial causes, primary and secondary neoplasms, communicating hydrocephalus, subdural hematoma, vascular lesions, migraines, cluster headaches, chronic paroxysmal hemicrania and hypnic headache. All other causes must be ruled out before the diagnosis of hypnic headache can be made.

References

1 Jeffrey D. Gould and Stephen D. Silberstein, Unilateral hypnic headache: A case study Neurology, Dec 1997; 49: 1749 - 1751.

2. Stephen d Silberstein Richared b Lipton Peter J, Headache in clinical practice 2nd edition Goadsby Martin Dunita Ltd 2002

3. http://ihs-classification.org/en/02_klassifikation/02_teil1/04.05.00_other.htmlISH Classification ICHD-II- Hypnic Headaches

4. Evers S, Goadsby PJ. Hypnic headache. Clinical features, pathophysiology, and treatment. Neurology. 2003;60(6):905–10. [PubMed]

5. Stephen D. Silberstein (Editor), Richard B. Lipton (Editor), Donald J. Dalessio Wolff's Headache and Other Head Pain Oxford University Press 2001