What should you know about sudden cluster headache?

Cluster headache is a neurological headache disorder marked by intense pain, often around one eye or the temple. The affected eye may water or redden, the eyelid may droop, and the nostril on that side may feel blocked or run. Attacks can begin abruptly and may make a person pace or feel unable to stay still. Similar symptoms can occur with other urgent problems, so a new pattern should not be self-diagnosed.

Stop driving and rest somewhere safe while arranging medical advice. Record when the pain started, how long it lasted, which side was affected, and any eye, nasal, nausea, or visual symptoms. Avoid alcohol during a cluster of attacks because it may trigger symptoms in some people. A clinician can distinguish cluster headache from other causes and discuss treatments that work quickly during attacks or help prevent further episodes.

Seek emergency help for a sudden explosive headache, new weakness or numbness, confusion, fainting, seizure, fever with a stiff neck, or new loss of vision. Get same-day assessment for a first severe attack, pain after a head injury, or headache with a painful red eye. A GP consultation can help assess a recurring pattern and decide whether specialist review is needed.

Could this pattern be cluster headache or another cause? What symptoms should make me seek emergency help? Which treatment should I use at the start of an attack, and how should I track triggers and timing?