Cluster headache

Attacks of extreme one-sided head pain, in clusters. Called suicide headache, and frequently misdiagnosed as migraine or sinusitis.

What it is

Cluster headache affects around 1 in 1,000 people, and it is regularly described by patients and clinicians as among the most severe pain there is. Women in studies who have experienced both have rated it worse than childbirth.

It causes attacks of excruciating pain, almost always on one side, around or behind the eye, lasting 15 minutes to three hours. Attacks come in clusters: several a day for weeks or months, then remission.

The characteristic feature is restlessness. Where somebody with a migraine lies still in the dark, somebody in a cluster attack paces, rocks, or bangs their head.

It is misdiagnosed as sinusitis, migraine or dental problems for years on average, and people undergo unnecessary sinus surgery and tooth extractions.

Signs you might notice

Severe, strictly one-sided pain around or behind one eye.

Attacks lasting 15 minutes to three hours, often at the same time each day, frequently waking the person around an hour after falling asleep.

On the same side: a watering red eye, a drooping eyelid, a blocked or running nostril, sweating, a smaller pupil.

Agitation and inability to keep still during an attack.

Clusters lasting weeks to months, then remission for months or years.

How it can affect day-to-day life

The nocturnal pattern destroys sleep for the whole cluster period, and the anticipation between attacks is its own burden.

Ordinary painkillers do nothing. Attacks peak too fast for a tablet to work, which is why the treatments are injected or inhaled.

The misdiagnosis costs are real: years of the wrong treatment while the attacks continue.

Alcohol reliably triggers attacks during a cluster and not during remission, which is a useful diagnostic feature.

Supporting someone well

Get the right acute treatment: high-flow oxygen through a non-rebreather mask, and subcutaneous sumatriptan. Both work within minutes and both are frequently not prescribed.

Push for home oxygen. It is effective, safe and under-prescribed, and it needs specific prescribing knowledge.

Ask about preventive treatment such as verapamil at the start of a cluster.

Avoid alcohol entirely during a cluster period.

Do not treat the restlessness as anxiety. It is a feature of the condition.

Ask for referral to a headache specialist rather than accepting a sinus or dental explanation.

Where to get help

Ask a GP for urgent neurology or headache clinic referral, and for oxygen and sumatriptan in the meantime.

OUCH UK, the Organisation for the Understanding of Cluster Headache, run a helpline and are the main UK source of expertise.

A first, sudden, worst-ever headache needs emergency assessment to exclude bleeding.