Hypnic headaches are a rare type of headache that occurs during sleep and wakes the person up, which is why they've earned the nickname “alarm-clock headaches".
Accordingly with Holle, the following are characteristics of HH:
Autonomic manifestations occurred in 7.6% of the patients, predominantly lacrimation (61.1%) and rhinorrhea (16.7%).
Based on observational studies, the most effective acute treatment is caffeine and prophylactic medications in use are lithium, caffeine, and indomethacin. Caffeine presented the best therapeutic response in acute treatment. In prophylaxis, lithium, caffeine, and indomethacin were effective drugs in 77.8% of the patients. (Silva, 2018).
Lanteri-Minet M. Hypnic headache. Headache. 2014 Oct;54(9):1556-9. doi: 10.1111/head.12447. Epub 2014 Sep 18. PMID: 25231430.
Holle D, Naegel S, Obermann M. Hypnic headache. Cephalalgia. 2013 Dec;33(16):1349-57. doi: 10.1177/0333102413495967. Epub 2013 Jul 5. PMID: 23832130.
Liang JF, Wang SJ. Hypnic headache: a review of clinical features, therapeutic options and outcomes. Cephalalgia. 2014 Sep;34(10):795-805. doi: 10.1177/0333102414537914. Epub 2014 Jun 18. PMID: 24942086.
Silva-Néto RP, Santos PEMS, Peres MFP. Hypnic headache: A review of 348 cases published from 1988 to 2018. J Neurol Sci. 2019 Jun 15;401:103-109. doi: 10.1016/j.jns.2019.04.028. Epub 2019 Apr 23. PMID: 31075680.