Cluster Headache

Pretty darn bad, apparently.

A cluster headache is one-sided head pain that may involve tearing of the eyes and a stuffy nose. Attacks occur regularly for 1 week to 1 year, separated by long pain-free periods that last at least 1 month.

They are "episodic" (most common) with 2 or 3 headaches a day for 1-2 months, brief HA free period and repeating pattern after that. The other type is "chronic" is about the same but without a period of sustained relief. Both are more common in men, and often feel like " an ice pick in the eye."

Of course it's always a good idea to see if the patient actually does have a pick in the eye before treating.