Cluster Headache: Care Staff Guide to Severe One-Sided Pain

Cluster headache is among the most painful headache disorders, yet it is often missed or mistaken for migraine or sinus problems. People with the condition may be pacing, rocking or unable to settle during an attack, which can look like agitation to those who do not know what they are seeing. This guide explains cluster headache for health and social care staff: how to recognise it, how specialists treat it, what staff should and should not do, and when severe headache needs urgent help.

What is cluster headache?

The NHS Dumfries and Galloway Right Decision Service, a clinical decision support resource for healthcare professionals reviewed in May 2025, describes cluster headache as a rare primary headache disorder. "Primary" means the headache is the condition itself rather than a symptom of another disease. The pain typically comes in bouts, or clusters, that last roughly two weeks to three months, with attacks occurring repeatedly during that time, followed by periods without symptoms.

Symptoms of an attack

The same source describes the typical features:

• severe pain on one side of the head, usually around the eye, forehead or temple
• untreated attacks lasting from about 15 minutes to 3 hours
• symptoms on the same side as the pain, such as a red or watering eye, a blocked or runny nostril, eyelid swelling, a small pupil, a drooping eyelid, facial sweating or flushing, and fullness in the ear
• restlessness or agitation, with the person unable to lie still

This restlessness is a key difference from migraine, in which people often prefer to lie quietly in a dark room. Staff should not interpret agitation during an attack as challenging behaviour. The person is in severe pain.

Triggers

The clinical guidance notes that smoking and alcohol may trigger attacks. It is worth recording what a person notices and sharing it with their clinicians. Do not encourage anyone to use alcohol or tobacco to cope.

When severe headache is an emergency

A known diagnosis of cluster headache does not mean every severe headache is cluster headache. Always treat a headache as a possible emergency if it is a sudden, severe "worst ever" headache, follows a head injury, or comes with fever, a stiff neck, a rash that does not fade, drowsiness, confusion, weakness, slurred speech, facial drooping or seizures. These can point to conditions such as meningitis, bleeding in the brain or stroke. Call 999 and follow your service's emergency procedure. Our guide to meningitis and septicaemia recognition explains the warning signs in more detail.

Getting a diagnosis

The Right Decision Service guidance recommends that everyone with suspected cluster headache is referred for specialist diagnosis. Because the condition is rare and the pain is so severe, it can take time to be recognised, and people may have been treated for other conditions in the meantime. Keeping a simple diary of when attacks happen, how long they last, which side is affected and what helped can speed up an accurate diagnosis.

How cluster headache is treated

Treatment is specialist-led, and care staff are not expected to select or adjust it. It is still useful to understand what is typically prescribed so you can follow the person's plan and spot problems.

Treating an attack. The clinical guidance describes subcutaneous sumatriptan, given by injection under the skin (6 mg, with a maximum of 12 mg in 24 hours), as a recommended option, with a nasal sumatriptan spray as an alternative. It also describes high-flow 100% oxygen, delivered by a mask for 10 to 20 minutes, which the guidance says is initiated by a consultant neurologist. The same source states there is no evidence to support opioids, anti-inflammatory painkillers, paracetamol or oral triptans for treating an attack. This matters in practice: ordinary painkillers are unlikely to help, and staff should not offer extra doses of over-the-counter medicines in the hope of relief.

Preventing attacks. Specialists may start verapamil during a bout, which the guidance notes is an unlicensed use. People taking verapamil need monitoring by their prescriber, so report side effects such as dizziness, swelling or an unusually slow pulse according to your service's procedure.

Medication-overuse headache. The guidance highlights the risk of medication-overuse headache, where frequent use of acute painkillers can itself cause headaches. Our guide to migraine and medication-overuse headache explains the risk in more detail. Make sure any as-required medicines are recorded accurately, and ask a pharmacist or prescriber to review them if use is frequent, in line with the medicines safety principles in our guide to polypharmacy and deprescribing.

Supporting someone during an attack

• Stay with the person, keep your voice calm, and do not insist that they lie down or keep still.
• Follow the person's individual treatment plan for medicines and oxygen exactly, and make sure staff using oxygen are trained and follow the safety instructions, because oxygen increases fire risk.
• Reduce noise and bright light if the person asks.
• Keep the area safe, since a person who is pacing or rocking in severe pain may bump into furniture.
• Record start and finish times, any triggers, and how well treatment worked.
• Do not minimise the pain or suggest it is "just a headache".

Living with a bout

Cluster bouts can disturb sleep and daily routines, because attacks often occur at predictable times, and living with the fear of the next attack can be draining. Staff should be alert to exhaustion, low mood and distress, offer a listening ear, and escalate concerns to the person's GP or specialist team. Support from headache charities and specialist nurses can also help people feel less alone.

Frequently asked questions

How is cluster headache different from migraine?

According to the clinical guidance, cluster headache causes severe one-sided pain with symptoms such as a watering eye and nasal congestion on the same side, and the person is typically restless. Migraine has a different pattern, so an accurate diagnosis from a specialist is important.

How long does a cluster bout last?

The NHS Dumfries and Galloway Right Decision Service describes bouts lasting around two weeks to three months, with each untreated attack lasting 15 minutes to 3 hours.

Can I give paracetamol or ibuprofen?

Only if the person's care plan or prescriber says so. The clinical guidance reports no evidence that these treat cluster headache attacks, and frequent use can cause medication-overuse headache.

Keep building your knowledge

Recognising uncommon neurological conditions helps teams respond with compassion and confidence. Explore the health and social care learning available through Learnsignal CPD to keep your knowledge current.

This article is general information for care staff, based on published NHS clinical guidance, and does not replace the advice of a person's own clinicians.