This headache has also been called “alarm clock” headache. These recurrent attacks occur only during sleep, causing wakening. They typically occur on 10 or more days per month for more than 3 months. The headache lasts 15 minutes and up to 4 hours after waking. This headache usually begins after age 50, but can occur in younger ages too. The pain is typically mild to moderate, but can be severe occasionally. The pain usually occurs on both sides of the head. There is no restlessness during the headache. There can be no autonomic symptoms [lacrimation (runniness/tearing of the eye), conjunctival injection (redness of the eye), facial sweating or flushing (skin turning blushed), nasal congestion, rhinorrhea (runniness of nose), sense of ear fullness, eyelid edema (swelling), or partial Horner’s syndrome (miosis (pupil becomes small)) and/or ptosis (droopiness of the eye)].