Cluster Headache

Cluster headaches are extremely painful headaches that occur in cyclical patterns or clusters, typically affecting one side of the head. They are usually accompanied by other symptoms like tearing, nasal congestion, or a drooping eyelid on the affected side. Each headache attack may last from 15 minutes to three hours, occurring frequently over several weeks or months, followed by remission periods. The exact cause is unknown, but they are thought to involve changes in the brain's biological clock. While they are less common than other types of headaches, their intensity can severely impact a person's quality of life.