What should you know about constant cluster headaches?

A cluster headache is typically severe pain on one side, often around or behind one eye. The same side may develop a watery or red eye, blocked or runny nose, eyelid swelling, facial sweating, or restlessness. Attacks can occur in a pattern over days or weeks, with pain-free periods between them, although patterns vary. A new severe headache should not be labelled cluster headache without assessment because migraine, sinus problems, eye conditions, and other causes can overlap. Keeping a record of timing, duration, side, eye or nose symptoms, and possible triggers helps the clinician.

Arrange a GP consultation for a new pattern, repeated attacks, or pain that is disrupting sleep or daily activities. Write down when each attack starts, how long it lasts, which side is affected, and any alcohol, heat, or strong-smell exposure before it. Use only medicines recommended for you; ordinary painkillers may not control cluster attacks. A clinician can assess the pattern and discuss an attack plan and prevention when appropriate.

Get emergency help for a sudden explosive headache, new weakness or numbness, trouble speaking, fainting, confusion, seizure, fever with a stiff neck, or vision loss. Urgent assessment is also needed for a painful red eye with reduced vision, a first severe headache during pregnancy or after childbirth, or a headache after a head injury.

Ask whether your attack pattern fits cluster headache, whether an eye or neurological examination is needed, which treatment should be used at the start of an attack, and what warning signs should send you to emergency care.