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Dr. Chrysoula I. Liakou MD, PhD
- Treated online: Assessment and urgent referral online; effective treatment (high-flow oxygen and injectable sumatriptan) is specialist-initiated, and the online role is recognition, a written urgent referral and bridging advice.
- What they are: attacks of severe one-sided pain around the eye lasting from a quarter of an hour to 3 hours, up to 8 times a day, with a red, watery eye on that side; about 1 in 1,000 people, men 3 times as often as women.
- Bouts: attacks come in clusters lasting 2 weeks to 3 months, often at the same time of year, with months or years free in between; about 1 in 10 people have the chronic form with no pain-free months.
- Triggers: alcohol can set off an attack within an hour during a bout, so it is avoided completely until the bout ends; strong smells, heat and broken sleep are common triggers, and attacks often strike 1 to 2 hours after falling asleep.
- Painkillers: paracetamol, ibuprofen and triptan tablets act too slowly for an attack that reaches full force in under 10 minutes, and opioids do not help; this is why specialist treatment is needed.
- Emergency: call 112 for a thunderclap headache, headache with fever, stiff neck or rash, or an attack with weakness, slurred speech, vision loss or confusion; a first-ever attack of excruciating eye pain needs prompt in-person assessment.
Call 112, do not book online, for a thunderclap headache (sudden, worst-ever pain peaking within about a minute), for headache with fever, a stiff neck or a new rash, or for headache with weakness, slurred speech, vision loss or confusion. A first-ever attack of excruciating one-sided eye pain also needs prompt in-person assessment, because a first attack cannot be safely labelled cluster headache over video alone.
What are cluster headaches?
Cluster headaches are attacks of excruciating pain on one side of the head, centred in or around one eye, lasting 15 minutes to 3 hours and striking up to several times a day in bouts that run for weeks. The eye on the painful side turns red and waters, and the nostril blocks or runs.[1] They are uncommon, and among the most painful conditions known to medicine; because effective treatment is specialist-initiated, online care focuses on recognition and rapid referral rather than treatment itself.
The name describes the timing, not the feeling. Attacks arrive in clusters: a bout of daily or near-daily attacks lasting weeks to months, then months or even years of complete remission. Many people get their bouts at the same time of year, and attacks often strike at the same hour, classically one to two hours after falling asleep, which is why cluster headache is sometimes called the alarm-clock headache. Around one in ten to one in five affected people has the chronic form, where bouts no longer switch off.[1] Men are affected more often than women, smokers more often than non-smokers, and the first bout typically arrives between the twenties and forties.[2][4]
How an online consultation helps with cluster headaches
- Recognition, often after years of mislabelling: cluster headache is regularly misdiagnosed as migraine, sinusitis or dental pain, and the average patient waits years for the right name. The attack story is distinctive, and a careful video consultation can capture it.
- An urgent referral that says the right things: the doctor writes a referral that names suspected cluster headache and flags the urgency, so neurology triage sees a condition with a specific, effective treatment pathway rather than another headache letter.
- Bridging advice that fits the condition: what to avoid during a bout (alcohol above all), why ordinary painkillers fail, and what to ask the specialist about, so the wait for the appointment is not wasted time.
- A safety net, not a sales pitch: if your story does not fit cluster headache, the doctor says so and tells you what it fits better; if it carries red flags, you are directed to emergency care immediately.
What the doctor checks in an online cluster headache consultation
The diagnosis rests on the attack story measured against international criteria, so the consultation is a structured interrogation of the pattern. The doctor will typically check:
- Attack length and frequency: untreated cluster attacks last 15 minutes to 3 hours and recur from once every other day up to eight times a day, a rhythm very unlike migraine or tension-type headache.[1]
- Strict one-sidedness and location: pain fixed in, behind or around one eye or temple, usually the same side in every attack of a bout.
- Autonomic signs on the painful side: a red or watering eye, a blocked or running nostril, a drooping or swollen eyelid, facial sweating or a smaller pupil.[1]
- Behaviour during an attack: restlessness and pacing point to cluster headache; lying still in a dark room points to migraine.
- Timing: night-time attacks at a predictable hour, bouts at the same season, and how long bouts and remissions last.
- Triggers within a bout: alcohol provoking an attack within an hour is characteristic during a bout, and typically harmless between bouts.
- Red flags: thunderclap onset, fever, neurological deficit, a first attack, or a changed pattern in someone with known cluster headache, all of which change the pathway.
- Health background for future treatment: heart disease, blood pressure, smoking and current medicines, because these shape which acute and preventive options the specialist can use.
How are cluster headaches different from migraine?
Cluster attacks are shorter, more frequent and behave differently: 15 minutes to 3 hours of strictly one-sided eye pain, up to several times a day, with a red watering eye and a blocked nostril, and an overwhelming urge to pace. Migraine attacks last 4 hours to 3 days, bring nausea and light sensitivity, and send you to lie still in the dark.[1] The distinction is not academic: triptan tablets and ordinary painkillers that help migraine are too slow for cluster attacks, and the treatments that do work are different. If your attacks last longer and come with nausea or aura, read the migraine treatment page instead; if you are not sure which pattern is yours, that question alone is a good reason to book, and the headache overview page compares the main headache types side by side.
Two rarer look-alikes matter because their treatment differs again: paroxysmal hemicrania causes shorter, more frequent attacks and responds specifically to indometacin, and trigeminal neuralgia causes electric-shock pains lasting seconds. Sorting these apart is specialist work, which is exactly why the referral matters more than a prescription here.
How are cluster headaches treated?
Guideline treatment of a cluster attack is high-flow oxygen through a non-rebreathing mask or a sumatriptan injection, both of which can stop an attack within about a quarter of an hour; standard painkillers such as paracetamol, ibuprofen and opioids do not work and waste the attack window.[2][3][5] Preventive treatment, most often verapamil, runs alongside during a bout. Because oxygen and injectable treatment need proper set-up and monitoring, treatment is initiated by specialist services.
It is worth being precise about why this page does not promise online prescriptions. Home oxygen is prescribed through country-specific supply arrangements with equipment, flow-rate and safety checks. Sumatriptan injections are usually started after specialist confirmation of the diagnosis. Verapamil for prevention is escalated to doses well above those used for blood pressure and requires ECG checks during dose increases, because it can slow the heart’s conduction.[2] Short steroid courses can bridge the gap while verapamil takes effect, and lithium, an option in chronic cluster headache, needs blood-level monitoring. These are exactly the treatments an honest online service coordinates rather than improvises: the doctors recognise the condition, refer you urgently, explain the pathway, and make sure nothing dangerous is missed while you wait.
Which cluster headache pathway fits your situation?
This is the decision framework the doctors use, aligned with cited European and UK guidance:[2][3]
Swipe sideways to compare →
| Presentation | Likely first step | Suitable for online care? | When referral or in-person care is needed |
|---|---|---|---|
| First-ever attack of excruciating one-sided eye pain | Prompt in-person assessment, usually with brain imaging at first diagnosis | No; a first attack needs examination | Always: first attacks are assessed in person to rule out other causes |
| Recurrent attacks matching the cluster pattern, never formally diagnosed | Video assessment of the attack story, then an urgent neurology referral for confirmation and treatment set-up | Yes, for recognition and referral | Specialist services confirm the diagnosis and initiate oxygen and injectable treatment |
| Diagnosed cluster headache, a new bout starting, specialist plan already in place | Review of the plan and bridging advice; the doctor coordinates with your existing specialist pathway | Often, case by case | Escalating bouts, a plan that has stopped working, or medication side effects such as dizziness or fainting on verapamil |
| Attacks with a changed character, or new symptoms between attacks | In-person reassessment rather than assuming the old diagnosis | Initial assessment only | Any new neurological symptom, or a pattern that no longer fits |
| Thunderclap headache, fever with stiff neck, weakness or confusion | Emergency assessment | No | Call 112 now; these are treated as bleeding, infection or stroke until proven otherwise |
Not sure which row is you? A doctor can tell you in one consultation.
See available times →Treatment options for cluster headaches
What you can do yourself
Honesty first: no pharmacy medicine reliably stops a cluster attack, and discovering that by trial and error wastes weeks of a bout. What does help is managing the bout itself. Avoid alcohol completely from the first attack of a bout to the last, because even small amounts can trigger attacks within the hour; between bouts it usually does no harm. Keep sleep regular, since disrupted sleep and napping can provoke night attacks. Some people find strong exertion or heat sets attacks off during a bout. Keep a simple log of attack times, length and side, which speeds up the specialist appointment considerably. If you smoke, this is a strong reason to stop, although stopping alone does not switch off a bout. During an attack, sitting upright or pacing in cool air feels more bearable than lying down for most people.
Prescription treatment
A prescription is never issued without a consultation, and for cluster headache most treatment decisions sit with specialist services: high-flow oxygen and sumatriptan injections to stop attacks, verapamil with ECG monitoring to prevent them, short steroid bridging courses, lithium with blood monitoring in chronic disease, and occipital nerve injections in resistant bouts.[2] What an online doctor can responsibly do is make the referral urgent and well-argued, explain each option so the specialist conversation starts further along, review whether an agreed plan still fits when a new bout begins, and prescribe within that plan only where the clinical picture allows. Opioids have no role in cluster headache and, like all controlled medicines, are not prescribed through online consultations.
Living through a bout
A bout is exhausting in a way that outsiders rarely grasp: weeks of daily attacks, broken nights and the dread between them. Plan around the predictability. Attacks at a fixed hour mean you can schedule work, driving and childcare defensively, and warn the people around you. Pain this severe is frightening and wearing, and saying so to a doctor is part of managing the condition, not a weakness; if the strain is building, the doctors take it seriously in the same consultation. The bout will end, and a named diagnosis with a treatment pathway genuinely changes the next one: people with confirmed cluster headache who reach a specialist leave with attack treatment that works within about a quarter of an hour rather than hours.
One practical European note: if a bout starts while you are travelling or living abroad, the referral pathway runs through the country you are in. An online consultation can map your story against the criteria in English, write the referral letter you hand to local services, and tell you what to do in the meantime, which is often the hardest part to arrange in an unfamiliar system.
When cluster headaches are assessed online, and when you need in-person care
Assessed online: recognising a cluster headache pattern from your attack history; writing an urgent, specific neurology referral; bridging advice for the current bout, including trigger management and what not to waste money on; reviewing an established specialist plan when a new bout starts, and prescribing within it when appropriate; and checking verapamil tolerability questions such as dizziness or a slow pulse, which are routed back to the prescribing specialist with the right urgency.
In-person care: every first attack, for in-person examination and usually imaging; every suspected new diagnosis, for specialist confirmation and initiation of oxygen and injectable treatment; any changed or atypical pattern in known cluster headache; chronic cluster headache needing preventive escalation, lithium or procedural options; and any red-flag presentation, which goes to emergency care by 112, not to a video queue. The consultation buys you speed and accuracy on the way to the right specialist, and the doctor says so plainly rather than prescribing painkillers that cannot work. Cluster headache is one condition within the headaches and migraines service, where the related attack patterns are covered in depth.
When to get in-person care
Call 112 for: a thunderclap headache reaching maximum intensity within about a minute; headache with fever, a stiff neck or a new rash; headache with weakness on one side, slurred speech, a drooping face, vision loss or confusion; or a severe headache after a head injury. Seek prompt in-person assessment, without waiting for a video appointment, for a first-ever attack of severe one-sided eye pain, for attacks that have changed character, or for a red painful eye with blurred vision, which can be acute glaucoma masquerading as cluster headache.
How Mobi Doctor works
- Book a time that suits you: open daily 7am–11pm CET. You can see a doctor over video, usually within 15 minutes. No subscription, exact price up front.
- Speak to a licensed doctor about cluster headaches: a private video call: you describe what you feel, the doctor asks what matters, and you agree the right plan together.
- Get your assessment, referral letter and bridging plan: any prescription follows the consultation when it is right for you. If your doctor decides you need to be seen in person, you get a full refund.
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Frequently asked questions about cluster headaches
What are cluster headaches?
Cluster headaches are attacks of excruciating pain centred on one eye or temple, lasting from a quarter of an hour to 3 hours and recurring up to several times a day, with a red, watery eye, a blocked nostril and a drooping eyelid on the same side. The attacks come in bouts of weeks to months with pain-free gaps between. They are rare, about 1 in 1,000 people, and treatable once recognised.
What does a cluster headache feel like?
A cluster headache feels like a stabbing or burning pain behind or around one eye that builds to maximum in under 10 minutes and is often described as the worst pain imaginable. Unlike migraine, it drives people to pace, rock or press on the eye rather than lie still. The eye reddens and waters, the nostril blocks or runs, the eyelid droops, and the attack ends as abruptly as it began.
What causes cluster headaches?
Cluster headaches come from activation of the trigeminal nerve pathway and the hypothalamus, the brain's body clock, which explains why attacks strike at the same times of day and the bouts at the same times of year. The underlying cause is not fully known; smoking and a family history raise the risk, and during a bout alcohol, strong smells, heat and disturbed sleep trigger attacks.
How do I know it is cluster headache and not migraine?
Length and behaviour separate them best. Cluster headache attacks last between a quarter of an hour and 3 hours, strike up to several times a day around one eye, make the eye red and watery, and drive you to pace. Migraine lasts 4 hours to 3 days, is usually one attack at a time, brings nausea and sensitivity to light and sound, and makes you want to lie still in the dark.
Why do ordinary painkillers not work for cluster attacks?
Because a cluster headache attack is too short and too severe for their speed. Paracetamol, ibuprofen and triptan tablets take 30 to 60 minutes to act, by which time the attack is ending anyway, and opioids do not help and carry real risks. Effective treatment acts fast: high-flow oxygen through a mask, or sumatriptan by injection or nasal spray, both working within a quarter of an hour.
How are cluster headaches treated?
Cluster headaches are treated in two ways: stopping attacks with high-flow oxygen through a mask or injectable or nasal sumatriptan, both of which work in most people within a quarter of an hour, and preventing attacks during a bout with verapamil, sometimes with a short steroid course or a nerve block to bridge the gap. These are started by a neurologist, which is why the referral is urgent.
Can an online doctor prescribe oxygen or sumatriptan injections for cluster headaches?
Not as a first step, and you should distrust any online service that offers to. Home oxygen for cluster headaches runs through supply arrangements set up by specialists, and injectable sumatriptan is normally started after specialist confirmation. What the online doctor does is recognise the pattern, write the urgent referral, and give bridging advice for the current bout.
How long does a cluster headache bout last?
A cluster headache bout typically lasts 2 weeks to 3 months, with attacks most days, then stops for months or years. Many people have one or two bouts a year, often in spring or autumn. About 1 in 10 develop the chronic form, with attacks continuing for a year or more without a month's break, which is treated with longer-term preventive medicines.
Are cluster headaches dangerous?
The attacks themselves do not damage the brain, but the pain of cluster headaches is among the worst in medicine and the toll of a bout is heavy, which is why the condition deserves urgent, properly organised care rather than endurance. The danger is in mislabelling: a first attack, or an attack with new features such as weakness, fever or a thunderclap start, must be assessed in person.
What can I do during a bout while I wait for a specialist appointment?
During a cluster headache bout, avoid all alcohol until the bout ends, keep your sleep schedule strictly regular, avoid strong smells and overheating, log each attack's time, length and side, and do not burn attacks on slow painkillers. Sitting upright and cold air on the face help some people a little. If an attack brings anything new, weakness, speech trouble, fever or a worst-ever start, call 112.
Can cluster headaches be prevented?
Cluster headache attacks within a bout are prevented with verapamil, started and dose-checked by a specialist with ECG monitoring, sometimes with a short steroid course or an occipital nerve block to cover the first weeks. Stopping smoking, strict sleep regularity and total alcohol avoidance during bouts reduce attacks. Between bouts no treatment is needed, and the next bout is treated early.
Are cluster headaches different in women or in pregnancy?
Cluster headaches affect men about three times as often, but in women they are frequently mistaken for migraine for years, so a clear description of one-sided eye pain with a watering eye and restlessness matters. In pregnancy, oxygen is the safest attack treatment and preventive medicines are chosen with the pregnancy in mind by the specialist, which is another reason for prompt referral.
- The International Classification of Headache Disorders, 3rd edition (ICHD-3): cluster headache criteria, IHS, International Headache Society, 2018.
- Headache, cluster: diagnosis and management, NICE Clinical Knowledge Summaries, National Institute for Health and Care Excellence, 2023.
- Headaches in over 12s: diagnosis and management (CG150), NICE, National Institute for Health and Care Excellence, 2012, updated 2021.
- Migraine and other headache disorders fact sheet, WHO, World Health Organization, 2024.
- Triptans for acute cluster headache, Cochrane, Cochrane Collaboration, 2013.
- Cluster headaches, NHS, National Health Service (UK), accessed October 2026.
This page is for information only and is not a substitute for a medical consultation. Guideline links are provided for transparency; treatment decisions are made with your doctor.
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