Cluster headache belongs to the trigeminal autonomic cephalalgias: the facial nerve (the trigeminal nerve) and autonomic nerve fibres are involved together. That explains the typical picture — fierce one-sided pain plus visible accompanying signs in the same half of the face, a watering eye for instance.¹ The name says what happens: cluster means an accumulation, and the attacks come in phases, building up over weeks to months — after which there can be a long spell of quiet. The pain is regarded as one of the most severe there is; unlike most headaches, an attack cannot be sat out.
Why getting the label right matters. Ordinary painkilling tablets have practically no effect in the short window of an attack — the right diagnosis changes the treatment fundamentally.
Episodic or chronic
The guideline distinguishes two courses:¹ in the episodic form — the more common one — active bouts lasting weeks to months alternate with symptom-free spells of at least several months. In the chronic form the attacks persist for more than a year without any appreciable break; it is rarer and harder to live with. One thing stands out: a seasonal regularity. In many people the bouts begin in spring or autumn — and anyone who knows that can discuss prevention in good time.
2. Symptoms: how an attack unfolds
The pain
The pain is strictly one-sided, sits around or behind the eye and often radiates into the temple, the upper jaw or the teeth. It climbs to its maximum within minutes, lasts 15 to 180 minutes untreated and often stops just as abruptly — within a bout that can mean anything from one attack every other day to several a day.
The accompanying signs on the painful side
These autonomic symptoms appear only on the side that hurts and are visible:¹,² a watering, reddened eye, a running or blocked nose, a drooping upper lid with a constricted pupil, sweating on the face. The running nose is what first leads many people to suspect a sinus infection.
The behaviour that gives it away
During an attack people cannot bear to lie still: they pace about, rock back and forth in a chair, press a hand against the eye. This restlessness is part of the condition — and it is the single most useful feature for telling it apart from migraine.
3. Cluster headache or migraine?
Both are one-sided, severe and come in attacks — and yet they are two conditions with different treatments. There is more on this in the article on migraine.
Feature
Cluster headache
Migraine
Side
Strictly one-sided, almost always the same side within a bout
Usually one-sided, can switch sides
Character
Boring, burning, behind the eye, maximal very quickly
Pulsating, throbbing, over a wider area, building more slowly
Duration untreated
15 to 180 minutes
4 to 72 hours
Frequency
Up to several times a day, often at night at the same hour
Single attacks, not several a day
Accompanying signs
Watering eye, running nose, drooping lid — on the painful side
Nausea, sensitivity to light and sound, sometimes aura
Behaviour
Urge to move: pacing about, restlessness
Withdrawal: quiet, darkness
Sex
Men more often
Women more often
Acute treatment
Oxygen, a triptan as a spray or an injection
Painkiller or triptan, tablets included
Table scrolls to the right
The question that reveals most. “What do you do during an attack?” — someone who lies down and switches off the light is more likely to have migraine; someone who paces about, cluster headache. Both can occur in the same person.
4. Causes, triggers and the role of sleep
The exact cause has not been settled. At the centre of it sits the hypothalamus — the brain region that also runs the body clock. That fits both the seasonal clustering of the bouts and the way the attacks keep to the clock.¹,³
The link with sleep: many attacks come at night, often one to two hours after falling asleep and at the same hour for weeks on end — see sleep disorders.
Alcohol: during an active bout even a small amount often sets off an attack within an hour. In symptom-free spells that effect is usually absent — a pattern that supports the diagnosis.
Nitrates, smells, altitude: medicines containing nitrates, strong smells, and also air travel and stays in the mountains count as triggers; a connection with smoking is known as well.
Think of medicines as triggers too. Vasodilating active ingredients, above all nitrates taken for heart conditions, can provoke attacks. Never stop them on your own initiative — take them to your next appointment, prepared as set out in the guide Preparing for a doctor’s appointment.
5. Diagnosis: why it often takes years
Cluster headache is a clinical diagnosis — it comes out of the pattern of attacks you describe, not out of a laboratory test. Anyone who does not know that constellation quickly lands on a different explanation.²,⁴
The sinuses: a running nose plus pressure behind the eye often leads to a working diagnosis of sinusitis — antibiotics included, which change nothing.
Teeth and jaw: because the pain radiates into the upper jaw, teeth are treated or pulled without any improvement — see toothache.
Migraine: the most common misclassification — with the result that people spend years taking tablets that cannot possibly work in time.
As a rule the work-up includes brain imaging on one occasion (MRI) to rule out other causes.¹
What to bring to the appointment. Note down over two to four weeks: the time an attack started, how long it lasted, which side, the signs at the eye and the nose, what you took and what it did. That often leads to the diagnosis faster than any investigation.
6. Acute treatment: oxygen and triptans
Acute treatment rests on two pillars. Both have to work very quickly, because the attack is often over after 30 to 60 minutes. That is exactly where conventional painkilling tablets fail. The choice of agent and the dose are always set by the treating practice.
Pillar 1Oxygen through a mask
High-dose oxygen
Inhalation of pure oxygen through a tightly fitting mask with a reservoir bag, sitting upright, right at the start of the attack. Many people affected report an effect within a few minutes. The benefit is well documented, and side effects are rare when it is used properly.¹,²
What many people do not know
Where cluster headache has been confirmed, oxygen treatment can be prescribed in Germany at the expense of the statutory health insurance — usually a device for the home, often with a portable cylinder as well. Raise the prescription yourself.
Limits
Oxygen does not work for everyone and not in every attack. With severe COPD special precautions are needed. Oxygen also feeds fire — smoking and naked flames are out of the question anywhere near it.
Pillar 2Triptans — in the right form
Sumatriptan as a pre-filled syringe
The injection under the skin counts as the fastest drug option during an attack. You are shown how to use it at the practice and then do it yourself. Details in the article Sumatriptan.
Triptans as a nasal spray
An alternative where the injection is not an option. The onset is as a rule somewhat later than with the injection, but well ahead of any tablet.
Why not tablets — and where the limit lies
A tablet usually takes longer to work than an attack lasts — it arrives systematically too late. On top of that, the product information sets maximum daily amounts. Anyone with several attacks a day runs into that limit quickly: another reason for oxygen and for effective prevention.
Triptans are not suitable for everyone. With coronary heart disease, after a heart attack or a stroke, with untreated high blood pressure and with certain vascular diseases they must as a rule not be used. Have this clarified medically before the first use — see also Drug interactions.
7. Prevention: verapamil, cortisone and alternatives
Because an attack that is already running can hardly be stopped, prevention is the heart of treatment. The aim is to bring down the number and the severity of the attacks within a bout. It is built up at the start of the bout and, once the bout has ended, tapered off in agreement with the practice.¹
Verapamil as first choice
Verapamil, a calcium channel blocker from cardiovascular medicine, counts as the standard for prevention here. Two points are often underestimated:
The dose is increased slowly. The amounts used for prevention are frequently above what is usual in heart medicine. That is why it is titrated up step by step and strictly to a medical plan.
ECG checks are part of it. Verapamil can slow conduction in the heart. That is why ECG checks are scheduled before the start and at every dose increase — part of the safety net, not bureaucratic extra.
A common trap. Verapamil does not work straight away — it usually takes one to two weeks before you notice an effect. Giving up in that time throws the benefit away. Talk to your practice before you change anything.
Cortisone to bridge the gap
To fill that waiting time a glucocorticoid such as prednisolone is often used for a few days up to a few weeks. It damps the attacks down quickly but, because of the side effects, is not a long-term solution — it is a short course with a defined end.
Never stop cortisone abruptly. After more than a few days of treatment cortisone is reduced step by step, because the body’s own production needs time to start up again. How tapering works is explained in the guide Stopping cortisone.
Further options
Nerve block at the back of the head: an injection of a local anaesthetic, sometimes with cortisone, can bridge a bout.
Lithium and topiramate: reserve options in chronic courses, both with laboratory monitoring.
Neuromodulation: at specialist headache centres in courses that resist treatment.
For CGRP antibodies, which have a firm place in migraine, the evidence in cluster headache is inconsistent; there is currently no European approval for that use. What makes sense in an individual case is decided by the treating practice.
Titrating verapamil, tapering cortisone, the ECG appointment
brite reminds you of every step and records what you took and when.
Anyone who lives for years with the wrong diagnosis eventually reaches for everything: ibuprofen, combination preparations, triptans, often in rising amounts. That can create a problem of its own — medication-overuse headache. If painkillers or migraine medicines are taken on too many days a month, an additional dull, persistent headache can build up that is barely separable from the underlying condition. For triptans and combination preparations the threshold is lower than for simple painkillers.²,³
An honest assessment. In pure cluster headache this risk is regarded as lower than in migraine. It becomes relevant above all where a migraine exists alongside it, or where someone has been treated for years for a supposed migraine. An overview of the active ingredients and their limits is given in Painkillers compared.
The lever is unspectacular but effective: count your treatment days — not the tablets, but the days in the month on which you took something for headache. That number is worth more in the consultation than any memory.
9. When the pain becomes unbearable
Because of its intensity, cluster headache is sometimes called the “suicide headache”. That is not a label but a pointer to a real problem: where attacks are very severe and frequent and the road has been a long one, despair, low mood and thoughts of not wanting to go on all occur more often than in the general population.¹,³ Those thoughts are a consequence of the pain and the exhaustion, not a personal failure — and a reason to get help.
Help in an acute crisis. If you have thoughts of taking your own life, contact Telefonseelsorge, the German emotional support helpline, straight away on 0800 111 0 111 or 0800 111 0 222 (free of charge, round the clock), the out-of-hours medical service on 116 117, or in an emergency 112 (emergency services in Germany) or the nearest emergency department. What can lie behind persistent low mood is described in our article on depression.
Raise the mental strain at your appointment. Effective prevention, an oxygen device and fast-acting acute medication often change the situation considerably — once there is control over the attacks, a sense of security usually comes back with it.
10. Everyday life during a bout
Leave alcohol alone during an active bout — it is then the most reliable trigger there is. What alcohol does to your medicines is set out in the guide Medications and alcohol.
Keep your sleep times steady — fixed times for going to bed and getting up, at the weekend too. Because the body clock is involved, shift changes are a problem for many people.
Keep the oxygen where the attack happens — by the bed at night, within reach in the daytime. A device in the cellar is of little use.
Keep an attack diary — time, duration, side, what you took, what it did. From the pattern, the start of the next bout can often be seen coming.
Do not stop prevention quietly — verapamil and cortisone in particular need an orderly plan, see the guide Stopping medications.
During a bout one rule counts double: regularity beats perfection. Forget the preventive treatment on some days and you often lose the benefit of the titration as well. Practical help for that in How to take medications.
How many attacks did you really have this month?
Progress, treatment days and effect — recorded instead of guessed.
The most telling thing is what you do during the attack: with cluster headache most people cannot bear to lie still and pace about, while with migraine they withdraw into a dark room. Add to that the short duration of 15 to 180 minutes and accompanying signs such as a watering eye or a running nose on the painful side. The classification is made by a medical practice.
Where cluster headache has been confirmed, oxygen treatment can be prescribed in Germany at the expense of the statutory health insurance. The usual arrangement is a device for the home, often with a portable cylinder as well. Many people know nothing about it — ask for it yourself.
Because a tablet as a rule takes longer to work than the attack lasts — it arrives systematically too late. That is why pre-filled syringes for injection under the skin or nasal sprays are used, which come up faster. Which form is suitable is decided by the practice.
On current understanding the hypothalamus is involved in how they arise — the brain region that also runs the body clock. That explains why attacks turn up at the same hour for weeks on end and often begin one to two hours after falling asleep. Steady sleep times are therefore worth keeping.
It is advised against. During an active bout even a small amount of alcohol often sets off an attack within an hour. In symptom-free phases that effect is usually absent. Take note of the alcohol warnings for your medicines as well.
Verapamil can slow conduction in the heart, and the amounts used for prevention are frequently higher than in heart medicine. That is why an ECG is scheduled before the start and at every dose increase. Titration happens only to a medical plan.
On current understanding there is no cure in the strict sense. The condition is, however, often treatable: effective acute treatment shortens the attack considerably, and suitable prevention brings the number down. In episodic courses there are often long symptom-free spells in between.
German S1 guideline on cluster headache and trigeminal autonomic cephalalgias (DGN, AWMF reg. no. 030-036) — German source. awmf.org
Gesundheitsinformation.de, German Institute for Quality and Efficiency in Health Care (IQWiG): Cluster headache. Accessed 2026 — German source. gesundheitsinformation.de
gesund.bund.de, the national health portal of the German Federal Ministry of Health: Cluster headache and headache disorders. Accessed 2026 — German source. gesund.bund.de
Medical disclaimer: This article is for general information and does not replace medical advice, diagnosis or treatment. Headache that is new, unusually severe or different in character from before, and headache with neurological deficits, fever or a stiff neck, needs immediate medical assessment — if in doubt through 112 (emergency services in Germany). If you have thoughts of taking your own life, get help without delay, for example from Telefonseelsorge, the German emotional support helpline, on 0800 111 0 111. The choice of medicine and its dose is always decided individually by the treating practice. Last updated: August 2026.
