Q: What is a Hypnic headache or an "alarm clock" headache?
Answer: a Hypnic headache is relatively an uncommon headache which may be benign but possibly a manifestation of an underlying tumor, particularly if occurs in later part of the life. It is called an "alarm clock" headache, as it happens only during the sleep and awaken the patient from sleep and persists for from 15 minutes to 3 hours. It exclusively never happens during the daytime. MRI is recommended to rule out any underlying tumor.
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