Headaches (Cluster)

Cluster headaches are a type of severe headache that affect the nervous system, specifically the nerves around the eye and temple. These headaches cause intense, one-sided pain that often feels sharp or burning. They usually occur in groups or clusters, happening several times a day for weeks or months, followed by periods without headaches. People with cluster headaches may also experience symptoms like a watery eye, nasal congestion, or drooping eyelid on the same side as the pain. The condition can significantly impact daily life due to the sudden and severe nature of the pain.

Cluster headaches are a primary headache disorder characterized by recurrent, severe unilateral periorbital pain lasting 15 to 180 minutes, occurring in clusters over weeks to months with remission periods. The pathophysiology involves activation of the trigeminal-autonomic reflex, leading to ipsilateral cranial autonomic symptoms such as lacrimation, nasal congestion, and ptosis. Hypothalamic dysfunction is implicated in the circadian and circannual periodicity of attacks. These headaches are more common in males and typically begin in adulthood. The disorder is distinguished by its excruciating pain intensity, short duration, and frequent daily attacks during cluster periods, making it one of the most painful headache syndromes.