G44: Other headache syndromes

G44.0: Cluster headache syndrome

The headaches usually occur at night and only on one side of your head. The headaches occur in bouts, and often last for several minutes or a few hours. The headaches are usually particularly severe around the eye and the temple. The eye or face may also turn red. The eye may water and the nose may run.

The cause of this type of headache is unknown. The headaches may occur more frequently when alcohol is drunk.