What sort of disease is a cluster headache?

BAD headache: A cluster headache is a relatively rare type of headache characterized by brief attacks of excruciating pain behind one eye and autonomic symptoms (watery eyes, runny nose, sweating). These headaches occur in series (clusters) of 1-8 per day (often like clock-work) that last for weeks or months. Extremely painful!

Severe pain : Cluster headache is considered the worst headache of human kind. Usually it affects men and associated with other symptoms, such as flushing of face, stuffed nose and drooping eye lead. Most probably the disease is related to the autonomic nervous system disorder.

What is a cluster HA: Cluster headache is a type of headache associated with autonomic nervous system symptoms, such as nasal congestion and tearing. It is considered a neurological disorder, possibly related to aberrant neuro-vascular signalling behind the face, on one side. It normally feels like a sharp pain behind one eye, occurring at the same time every day, for several days.