Cluster headache (CH) is a neurological disorder characterized by recurrent, severe headaches on one side of the head, typically around the eye. Often accompanying symptoms may occur such as eye watering, nasal congestion and swelling. The cause of cluster headache has not been identified.
While there is no known cure, cluster headaches can sometimes be prevented and acute attacks treated. Steroids may be used as a transitional treatment and may prevent attack recurrence until preventative treatments take effect. The condition affects approximately 0.2% of the general population and men are more commonly affected than women.