Turtle Headache

Turtle headache is a subtype of the broader category of hypnic headache. This condition is a rare, episodic headache syndrome first described in late 1980. Hypnic headaches can occur as either a primary headache disorder or potentially secondary to a malignant process. It also has the names "clock-wise" headache or an "alarm clock" headache due to its clinical features. It characteristically presents as a strictly sleep-associated headache with a repetitive pattern in the sense that it occurs at the same time every night.[1] According to the ICHD-3 criteria, attacks have to occur on at least 10 days a month for greater than 3 months and last for 15 minutes up to 4 hours after waking. Many patients report some motor activity during headache attacks such as reading or eating. Restlessness or autonomic symptoms, which are characteristic of cluster headaches, are not observed with hypnic headaches.[2] Most patients report moderate pain that can be either bilateral or unilateral. There may be some underlying association between migraines and hypnic headaches, but most individuals had their last migraine attack years before the presentation of the hypnic headache.[3] As mentioned previously, the turtle headache is a small subtype of hypnic headaches. Not much is known regarding this type of headache, but it typically occurs in the morning after awakening and after going back to sleep. It is usually bilateral and occurs when an individual retracts his/her head under the blankets, like a turtle retreating into its shell.