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cluster headache
cluster headache Cluster headache is a primary headache disorder marked by very severe pain on one side of the head, usually around the eye, forehead, or temple.
Cluster headache is a primary headache disorder marked by very severe pain on one side of the head, usually around the eye, forehead, or temple. Attacks last about 15 to 180 minutes, can happen from once to eight times a day, and often come with same-side eye redness or tearing, nasal symptoms, facial sweating, eyelid swelling, or a constricted pupil.