About This Condition
Cluster headaches are very painful one-sided headaches that tend to occur in clusters of several headaches in a short period of time, after which there may be no headaches for weeks or months. Cluster headaches that continue for more than one year without remission, or with remissions lasting less than 14 days, are considered to be chronic and are very difficult to treat.
Cluster headaches involve pain in the eye or upper face, tearing, runny nose with nasal congestion, and facial sweating.1
Oxygen inhalation is especially beneficial when symptoms occur at night.