Cluster headache

Cluster headache is a primary headache disorder affecting approximately 0.1% of the population. It is characterized by intense unilateral headache attacks accompanied by symptoms such as swelling of the face or watering of one eye. The attacks can last up to 3 hours and occur up to 8 time per day. 85% of patients suffer from episodic cluster headache, consisting of attacks in clusters (or "bouts") of a week to a year (mostly two weeks to three months), interrupted by attack-free phases of remission lasting three months to years. The remaining 15% of patients who suffer from chronic cluster headache experience no remission phases (or shorter than three months).

Further reading

• Cluster headache pathophysiology — insights from current and emerging treatments (Wei and Goadsby, 2021)
• Current treatment options for cluster headache: limitations and the unmet need for better and specific treatments—a consensus article (Lund et al., 2023)
• The economic and personal burden of cluster headache: a controlled cross-sectional study (Petersen et al., 2022)
• Cluster headache is one of the most intensely painful human conditions: Results from the International Cluster Headache Questionnaire (Burish et al., 2021)
• The genetics and chronobiology of cluster headache (Belin and Barloese, 2023)