Hypnic Headache: A Rare Type of Primary Headache Disorder

Hypnic headache is a very rare type of headache. It is more common in people over the age of 60. It occurs during the night and wakes the patient, hence the name “alarm clock headache.” It is usually unilateral and lasts between 15 minutes and 4 hours. Unlike Cluster Headache, Hypnic Headache is usually dull in character and does not make the patient restless. Most patients do something after waking up. Rhinorrhea, tearing, and ptosis are not associated with hypnic headache. The majority of diagnosis is clinical. Secondary causes of headache must be ruled out before making a Hypnic headache diagnosis. The International Classification of Headache Disorders, Third Edition (ICHD-3)-beta includes diagnostic criteria for hypnic headache.

Hypnic Headache is a very rare type of primary headache. Clinical trials are needed to find out its pathophysiology and proper treatment option.

Mr. X is a 70-year-old patient who has been complaining of headaches while sleeping for the past year. The headache began 3 to 4 hours after falling asleep. He wakes up from sleep almost every night between 03:00 and 04:00 a.m. due to a headache. His headache lasted 30 to 40 minutes. He was too embarrassed about his sleep disturbance. He keeps himself busy with some routine and religious activity after waking up from sleep, and the headache gradually resolves. He then returns to his bed. Mr. X also stated that the headache is dull in nature and is located in the left temporooccipital region. Headache is not associated with photophobia, phonophobia, nausea, vomiting, tearing, or leg discomfort. He has no history of early morning or daytime headaches, sleep disorders, snoring, or sleep apnea. He has no history of head trauma, fainting, unconsciousness, limb weakness, or seizures. He is a non smoker, non hypertensive, and non diabetic patient [1].

On general examination, his heart rate is 70 beats per minute and his blood pressure is 138/68 mm of Hg. There is no anemia, jaundice, or oedema. Both lung fields are clear. Neurological examinations reveal no abnormalities. His serological tests, CBC (Complete Blood Count), FBS (Fasting Blood Glucose), and lipid profile are all within normal limits. CT scan of the brain is normal [2]. There is no evidence of cerebral atrophy or volume loss associated with aging. Mr. X was given paracetamol, diclofenac sodium, mefenamic acid, and tramadol hydrochloride by several general practitioners. He used these drugs either alone or in combination. However, there was no significant improvement with this treatment. Mr. X is terrified and depressed as a result of his nocturnal headache (Figure 1).

Figure 1:

The pathophysiology of hypnic headache is not well understood. Bedtime coffee, lithium carbonate, and indomethacin are common treatment options for hypnic headache [3]. Our patient meets all of the criteria for hypnic headache and improves with Indomethacin 50mg in divided doses [4,5].

Hypnic Headache is an extremely uncommon type of primary headache. Delays in diagnosis and treatment can occur due to a lack of research and awareness about these disorders.

None.

No Conflict of interest.

1. Raskin NH (1988) The hypnic headache syndrome. Headache 28: 534–536.
2. Evers S, Goadsby PJ (2003) Hypnic headache: clinical features, pathophysiology, and treatment. Neurology 60: 905-909.
3. Stefan E, Peter JG (2005) Hypnic headache. Pract Neurol 5: 144-149.
4. Dodick DW, Mosek AC,  Campbell  JK (1998)  The  hypnic  (“alarm  clock”) headache syndrome. Cephalalgia 18: 152-156.
5. Headache Classification Subcommittee of the International Headache Society (IHS) (2018) The International Classification of Headache Disorders, 3rd edn. Cephalalgia 38(1): 1–211