Dangerous Headaches?
16 Symptoms You Cannot Ignore
Dangerous Headaches are usually headaches of recent onset in someone who has never previously had a headache.
Dangerous Headaches sometimes happen to people with Migraine or Tension-Type Headache. The difference is that dangerous headaches are new and very different.
Before you start looking for answers to your headache problem you need to know that you are safe.
The 16 Patterns that could indicate Dangerous Headaches
Most people with these present to an emergency room as it is obvious to them that something is not right. (The overall chance of a dangerous cause is in brackets).
- Sudden Severe Headache Out of The Blue: Thunderclap Headache (10-15%)
- New Onset Headache with a New Onset of Fever (5%)
- Headache with Progressive Neurological Symptoms or Signs (5-10%)
- Postural Type (Orthostatic) (30%)
- Exercise Induced (20%)
- Cough Induced (10-20%)
- With Pulsatile Tinnitus (20%)
- New onset With a Previous History of Cancer (10%)
- With Known HIV Infection (10%)
- Headache with loss of menstrual cycle / loss of libido (5%)
- New onset in your 50s or over with weight loss and scalp tenderness (30%)
- A New Headache In Wintertime or after Electricity Black Out (10%)
- Cluster Headache of recent onset(<5%)
- Bouts of severe facial pain called Trigeminal Neuralgia (10%)
- Severe headache with a Body Mass Index over 40 (5-10%)
- A Chronic Headache that is completely out of control (0.05%)
Always remember to seek medical advice for symptoms causing you concern.
Headaches lasting more than 6 months are unlikely to be dangerous headaches.
Dangerous Headaches will have significant features mentioned in this guide.
1. Sudden Severe Headache Completely Out of The Blue- Thunderclap Headache
Thunderclap Headache is severe and appears suddenly. At it’s worst from the very start, it comes out of nowhere. Until that point you will never had anything as bad ever.
Thunderclap Headache usually affects the whole head. It does not build up over hours like a Migraine. The pain is at its peak within 2 seconds ….1….2……BOOM!
A Thunderclap Headache will persist for several hours before settling down.
The most common headache mistaken for Thunderclap Headache is a brief, severe, sharp pain called Ice-Pick Headache. Ice-Pick Headache usually happens in or around one eye. It is away as quick as it came, and is an example of a ‘Neuralgic’ Pain.
The most important question to ask is “from the start of the headache until it reached its worst – how long did that take?”
Doctors miss Thunderclap Headache when the onset isn’t discovered as sudden and severe. This can lead to serious harm, so always be clear about the exact onset of a new headache.
What Causes Thunderclap Headache?
Thunderclap Headache is due to ‘Subarachnoid Haemorrhage’ in about 10% of people. Most people with ‘Subarachnoid Haemorrhage’ have had a ‘Berry Aneurysm’. A Berry Aneurysm is a weakness in the wall of an artery which bursts to cause bleeding.
Thunderclap Headache needs IMMEDIATE medical advice. Normally a CT Brain Scan is needed as soon as possible. If a CT Brain Scan is normal you need a Lumbar Puncture Test , and even an angiogram or venogram test of brain blood vessels.
Causes of Thunderclap Headache – the longest list on the planet (Links to Facebook)
What is the most important thing to know about Thunderclap Headache?
The time from start to maximum pain.
The Difference between Thunderclap Headache and Ice-Pick Headache
Ice-pick Headaches also cause sudden severe headache that is at its worst from the start. However, Ice-pick Headache usually affects a small part of the head only – most commonly in or around one eye – and only lasts a few seconds.
Ice-Pick Headaches are very common – maybe 20,000 people per million get Ice-Pick Headaches each year, compared to 400 people per million with Thunderclap Headache.
Repeated Episodes of Thunderclap Headache
It is possible for Thunderclap Headache to return repeatedly over several weeks or months. When it returns, emotion, exertion or a specific scenario like having a very hot bath may be the reason. Sexual Activity causes repeated attacks of Thunderclap Headache.
‘Reversible Cerebral Vasoconstriction Syndrome (RCVS)’ is the most likely cause of repeated Thunderclap Headache. RCVS makes brain arteries go into spasm, and the spasm causes the sudden severe pain. Up to 60% of people with Thunderclap Headache may have some form of Reversible Cerebral Vasoconstriction Syndrome.
One-Sided Thunderclap Headache
A sudden severe headache on one side of the head needs investigation. The cause depends on the location of the pain and examination findings. A sudden onset of severe pain in one eye or one side of the forehead can indicate a Carotid Artery Dissection.
Carotid Dissection usually causes the upper eyelid on the same side as the pain to drop a couple of millimetres. You can check if an eyelid position is old or new by comparing with old photographs.
People may describe a ripping sensation in the head or neck at the start of the pain. The pain that persists is often throbbing in nature and feels really severe.
If a similar pain occurs in the back of the head, then the artery at the base of the skull called the Vertebral Artery may have torn – called Vertebral Artery Dissection.
Most people with dissection make a full recovery – the artery heals itself up.
However, a tear in the lining of an artery can lead to a stroke. Some types of dissection can also lead to a rupture of the artery causing brain haemorrhage.
Sudden, one-sided headache, followed by symptoms of weakness, speech loss or visual loss could be due to a stroke. Suspected stroke needs immediate medical attention.
Many people with sudden, one-sided headache have normal tests. In this situation the most likely cause is pain referred from the jaw joint (TMJ) or Upper Cervical Spine. Pain referred from the upper cervical spine is called Cervicogenic Headache and some people call it Occipital Neuralgia.
2. New Onset Headache with New Onset Fever
One of the most feared dangerous headaches is suspected Meningitis. In Meningitis there is a new onset headache with fever. For every 10 people with Meningitis, 9 will have ‘Viral Meningitis’ and 1 will have a much more dangerous cause called ‘Bacterial Meningitis’.
There is a 10% risk of meningitis being found in someone attending an Emergency Room with new onset of headache and fever.
30% of survivors of Bacterial Meningitis will have a significant neurological problem, and the overall risk of death is about 10%. Bacterial Meningitis must be treated as an emergency, as early treatment reduces the risk of harm.
The Headache of Meningitis
In Viral Meningitis the headache usually follows a day or two of feeling run down – like you have a viral illness. The pain in the head can build up at the same time as the main illness. Alternatively you experience a much more sudden build up of headache after a few days of feeling run down and hot.
Neck stiffness is also a common symptoms that accompanies the headache.
At the same time, you will feel very hot and may have other symptoms of a viral illness eg aching limbs, sore throat, cough, nasal congestion.
The headache of Bacterial Meningitis is a progressive headache. However most people with Bacterial Meningitis develop the headache over a few hours before feeling so ill that they get help. Half of people with Bacterial Meningitis will be in hospital within 24 hours of their first symptom.
Bacterial Meningitis is a much more severe and dangerous headache than Viral Meningitis and needs immediate antibiotic treatment.
95% of people confirmed as having bacterial Meningitis have at least 2 of the following 4 symptoms:
headache; neck stiffness; fever; altered mental status.
Other important symptoms that can appear alongside the headache of Bacterial Meningitis include: weakness, rigors, extreme exhaustion and a new rash.
People with any type of Meningitis can get a sudden severe Thunderclap Headache – this is why a Lumbar Puncture should be performed when investigating a new sudden severe headache.
What does the Headache of Meningitis Feel Like?
The pain of Meningitis is very difficult for the patient to describe – it is just very severe and will feel like the worst headache they have ever had. It can described as a pressure – like the head wants to burst. It can also be a severe all-over throbbing pain.
Almost everyone with Meningitis will say that it is sore to look at light – called Photophobia. The pain of Meningitis can sound like Migraine, but in Meningitis there is a fever present.
People with Meningitis do not get significant relief from standard painkillers – at which point medical advice is usually sought. Usually the whole head is involved – it is not normally a one-sided pain.
How can I tell the difference between Migraine and Meningitis?
Telling the difference between Migraine and Meningitis is difficult. Many people with Migraine will have had the experience of being admitted to hospital to have tests for Meningitis.
Both types of headache are severe, throbbing and you want to avoid light. Vomiting occurs in both.
In someone with a previous history of Migraine it is hard to know if this is Migraine or Meningitis. If in doubt a doctor will usually manage the headache as Meningitis until they can rule it out. The short answer is that there is no easy way to tell the difference – it’s usually safety first. In Migraine the tests will be normal.
Systemic Illness Headache – The Most Common Cause of Headache and Fever
Most people with new onset of headache and new onset of High Temperature have an infection which will go away itself. This is called ‘Systemic Illness Headache’.
A common cause would be Influenza (The ‘Flu’), various types of pneumonia or upper respiratory tract infection. The headache will usually feel like a pressure or throbbing pain. The clue that it is not Migraine or Tension-Type Headache is that the high temperature alongside the pain. As the fever settles, so does the headache.
As many as 80% of people with this type of infection of the nervous system will report mild headache during their illness – and tests will not show evidence of meningitis.
3. Headache with Progressive Neurological Symptoms or Abnormal Neurological Signs
A focal neurological symptom is a symptom caused by abnormal activity in the nervous system.
Blurred vision, double vision, tingling or numbness, weakness of face, arm or leg, vertigo, and loss of speech are focal symptoms.
A focal neurological sign is an abnormality of body structure or function observed by a doctor (or optician) during a neurological or eye examination.
How the face muscles, arms or legs move, or how the reflexes react are also examples of neurological signs.
Changes in patterns of eye movement, the shape of the pupils, position of the eyelids, the shape or colour of the optic disc or retina are also signs. A doctor or optician would identify these eye signs.
A neurological and eye examination is a very important part of assessing a person with headache. Any new headache accompanied by abnormal neurological signs is potentially one of the dangerous headaches.
What pattern of Headache with Focal Neurological Symptoms is dangerous?
Dangerous Headaches have progressive neurological symptoms. The neurological symptoms start slowly – maybe over several weeks and continue to get progressively worse. With each passing week there is worsening loss of vision, loss of speech, weakness or confusion.
A progressive focal symptom like this can be a symptom of Brain Tumour or an infection of the brain called encephalitis. A blocked vein within the head – called cerebral venous sinus thrombosis, can also present as one of the dangerous headaches.
The headaches experienced by people with Brain Tumours, encephalitis or blocked veins in the head can all sound just like Tension-Type Headache – eg an intense pressure, and will sometimes throb. Nausea or intolerance of light can sometimes occur.
Migraine with Aura: The Most Common Cause of Headache and Focal Neurological Symptoms
About 12% of all adults will experience Migraine. About 1 in 5 people with Migraine will experience Migraine Aura. This means that 1 person in every 40 will experience Migraine Aura (here’s the arithmetic: 12.5% time 20% = 2.5% or 1 in 40).
In Migraine Aura there is a gradual build up of visual loss, abnormal sensation, weakness or speech disturbance over 5-20 minutes, which can last another 20-120 minutes before going away completely.
About 1 person in 5 with Migraine will experience Migraine Aura. Migraine Aura can happen just before the pain of a Migraine Headache, but can also happen on its own between Migraine Headaches (called Isolated Migraine Aura).
Migraine Aura is due to a protective electrical change in the surface of the brain called ‘Cortical Spreading Depression’. This protective response spreads slowly across the surface of the brain and is now understood as the reason for Migraine Aura.
Migraine Aura with Headache is not dangerous. However, someone who only ever gets Migraine Aura and NEVER has any headache will need investigated further. Migraine Aura on its own – especially if it appears in later life – 60’s or older – can be a symptom of a focal brain disease such as a minor stroke.
How do Migraine Aura and Brain Tumour differ?
The difference between is not the nature of the headache – it’s the nature of the focal neurological symptoms that come along with the headache.
Migraine Aura will build up over minutes, last minutes to an hour or two, then settle. The focal neurological symptoms of a brain tumour will start over days and build to their worst over several weeks. When examined, a doctor will identify abnormal signs, or be sufficiently concerned about the progression of symptoms that tests are arranged.
New Onset Headache with Short Lived Focal Neurology
Some people will develop a focal symptom a bit like this: the hand or foot will start to claw or tighten, and then within a few seconds start to shake or stiffen. The shaking or stiffness can spread from foot to hand, or hand to foot or even to one side of the face. This pattern of movement would make me suspicious of a partial epileptic seizure.
A partial epileptic seizure, of new onset always needs investigated. In adults a partial epileptic seizure happening for the first time has a 10% risk of an underlying serious problem such as a Brain Tumour.
Everyone with focal epileptic seizures needs to seek medical advice to get treatment to reduce the risk of further epileptic seizures.
What do Brain Tumour Headaches Feel Like?
The classic Brain Tumour headache is due to the fact that a large Brain Tumour will start to take up too much room inside the head. This creates a high pressure situation which stretches pain-sensitive structures like the lining of the brain or blood vessels in the brain. The jargon term doctors use is an ‘SOL” – a Space-Occupying-Lesion.
A classic ‘SOL’ headache is actually very rare.
People who have Brain Tumours and Only have Headache.
Only 2% of people with Brain Tumours will have headache – AND ONLY HEADACHE – by the time they are diagnosed.
Even then most Brain Tumour Headaches sound like Tension-Type Headache.
In Brain Tumour Headache other focal symptoms start to appear within about 8-10 weeks. Long standing headaches with no other symptoms and normal neurological and eye examinations are not caused by Brain Tumours.
In people with Brain Tumours there is a significant clue on neurological examination – swelling of the back of the eye, or an abnormal neurological sign affecting eye movement, balance, speech or strength.
Classic Brain Tumour Headaches are Rare
Only 1/16 Brain Tumours which present with headache have classic ‘SOL’ (Space Occupying Lesion) Headache. A classic ‘SOL’ headaches is a headache that wakens from sleep and causing unprovoked vomiting.
As the day goes on – when you are up and about – the headache improves, only for it to be repeated the next morning.
The reason a classic ‘SOL’ headache is worst in the morning is that pressure inside the head rises when you lie flat, so by morning time pressure reaches its peak and symptoms appear.
The Maths of Brain Tumour Headaches
Each year about 140 out of every million will suffer a Brain Tumour.
Of these about 2% will only have headache and nothing else – no focal neurology.
That means the chance of a new onset headache being due to a Brain Tumour is roughly 3 per million.
Tension-Type Headache will affect about 40% of the population each year. The chance of a new onset headache being Tension-Type Headache is about 400,000 per million.
A new onset headache is over 100,000 times more likely to be Tension-Type Headache than a Brain Tumour Headache. The risk is even smaller if you have a normal neurological and eye examination.
4. A New Onset Headache which is Postural – ‘Orthostatic Headache’
This is a new onset headache – usually affecting both sides of the head like an intense pressure or squeezing. What makes this headache notable is that when you lie down flat the pain goes away completely.
Within no more than a minute your head feels clear. When you go to sit up or stand up again within a minute it’s back again – a tight, intense squeezing pain on both sides of the head. You lie down again the headache is better.
This pattern of new onset headache, which changes with posture is also called an ‘Orthostatic Headache’. It is the classic headache of low pressure inside the head.
Other symptoms that usually come at the same time are disturbances of hearing – tinnitus or distorted hearing, and very often there is neck pain or pain between the shoulder blades.
Classic Orthostatic Headache is rare, but if present has a high (>30%) chance of being due to a low pressure problem. The danger with low pressure headache is that it is completely incapacitating, yet can be treated effectively with an ‘epidural patch procedure’.
Diagnosis of low pressure can be very difficult and requires a contrast enhanced MRI scan of the head. Changes are usually present on a plain non-contrast MRI but are easily overlooked. A CT Brain Scan is usually normal, unless the low pressure is so severe that it has caused a build up of fluid in the side of the head called sub-dural collections.
5. New Onset Exercise Induced Headaches
A Headache that is only ever brought on by exercise or straining should be investigated, as this type of headache has a 20% chance of an underlying cause.
Exercise headache is provoked by physical activity, which could be anything from running, rowing, cycling, lifting weights or climbing stairs.
Sexual activity can also provoke this pattern of headache – usually at the height of sexual excitement there is a sudden severe headache – similar to Thunderclap Headache.
An Exercise Induced Headache feels like an intense throbbing or pressure pain building up within seconds or minutes of starting exercise.
The pain is usually on both sides of the head, or feels like the whole head is about to explode, and can last from 5 minutes to a couple of days.
In some people the pain evolves into a pain very similar to a migraine – throbbing quality of pain with intolerance of light, noise, smell or movement – in which case the term exercise induced migraine is used.
A first ever Thunderclap Headache which is brought on by exercise needs to be managed in the same way as a spontaneous Thunderclap Headache – immediate medical attention in an Emergency Room is required.
Causes of Exercise Induced Headaches
Most people with Exercise-Induced Headaches have several bouts of the headache before seeking medical advice. These headaches still need investigated. After several episodes the risk of a very serious cause such as brain haemorrhage is very small. After a first episode, especially if it was Thunderclap Headache, the risk of a dangerous cause is greater than in someone who has had several episodes.
In older people Exercise Induced Headache can also be a symptom of angina – that is heart disease and is called cardiac cephalalgia. Older people with Exercise Induced Headaches should also be tested for heart disease (coronary artery disease). In this case it’s heart disease not brain disease making this a dangerous headache.
The 2 most common causes of Exercise Induced Headaches are a developmental abnormality called Chiari Malformation and Low Intracranial Pressure (Spontaneous Intracranial Hypotension). The risk of finding one of these causes of an exercise-induced headache is about 20%.
An Exercise Induced Headache needs investigated as it can be a symptom of either very high or very low pressure inside the head.
A first ever episode of sudden headache during sexual activity will need immediate investigation to rule out more serious causes – similar to the approach with Thunderclap Headache. Repeated sudden headaches brought on by sexual activity do not often have a serious cause identified but are probably due to brain blood vessel spasm called Reversible Cerebral Vasoconstriction Syndrome.
If a cause is not found then the condition is labelled ‘Primary Exertional Headache’.
6. New Onset Cough Induced Headaches
This rare pattern of headache goes like this: you are completely pain free until you cough. At the point of coughing there is a sudden and usually severe impulse of pain or pressure in the head – like being hit with a blunt object.
You feel stunned briefly, and the pressure or pain settles down after about a minute. Nearly every time they cough – they get the same experience.
The pain usually feels like it affects the whole head, but it can be just the back of the head or feel like it is the front of the head. The location is not specific.
A cough-induced headache has all the same causes and need for investigation as a Exercise-Induced Headache – mentioned above.
The classic cause of a cough induced headache, exclusively induced by coughing, is Chiari Malformation. Low Pressure inside the head – called Spontaneous Intracranial Hypotension – can also cause a cough induced headache, although postural headache is present as well.
People with Chiari Malformation will also describe headaches provoked by laughter or changes in position eg stooping forward to pick something off the floor.
Cough Induced headaches need investigated – an MRI is required to be certain about the presence or absence of Chiari Malformation.
One Sided Cough Induced Headaches and Coughing During a Migraine
There are people with cough induced headaches that are one sided. In my experience these patients will often have evidence of stiffness of joints in the upper part of the neck. Cough induced pain is likely to be referred from the upper cervical spine. The mechanical stimulus of coughing refers pain up the back, side and front of one side of the head.
During a Migraine Attack pain in the head will worsen if you cough or move. This is a worsening of pain and is different from Cough Induced Headache where there is no pain…until you cough. This is an important difference as people can end up undergoing unnecessary investigations or hospital admissions if a Migraine is misdiagnosed as a Cough Induced Headache.
7. New Onset Headaches with Pulsatile Tinnitus
Pulsatile tinnitus describes a whooshing noise in the head which is in time to your pulse – so if you feel your pulse the noise in your head is going at exactly the same rate.
Incidentally, pulsatile tinnitus, without headache, also requires investigation in case there is a problem with blood vessels close to the inner ear.
When pulsatile tinnitus is present with a new onset and persisting headache the most common cause is a condition of high pressure inside the head called Idiopathic Intracranial Hypertension.
The typical Intracranial Hypertension Sufferer is a female of 20-30 years of age who is overweight (BMI of 30 or more).
The headache is usually an intense pulsating feeling at the front (both sides) or an all over headache. To the sufferer this will usually feel like a dangerous headache and different to any previously encountered headache.
The pain can be made worse by straining, exercise or stooping forward or coughing, and when the pain worsens the pulsatile tinnitus is often louder. The headache can waken the sufferer. Some people describe a pain restricted to the back of the head, and one in 3 people vomit with the headache. It is rare for this headache to be one-sided.
Sometimes the pressure in the head will evolve into a typical Migraine Headache with nausea, photophobia and intolerance of noise.
Visual Complications of High Pressure Headaches
High pressure over many weeks can damage the optic nerves – which carry light from your eye to the brain. A Visual Field Test is needed to see if optic nerve damage has occurred. It is the risk of visual loss that makes this one of the dangerous headaches.
Over 70% of people with Intracranial Hypertension will report brief episodes of near-complete visual loss on straining called a visual obscuration – which should alert the doctor to a possible high pressure problem.
The best clue that high pressure is present comes from examining the back of the eye and seeing swelling at the point where the optic nerve joins the back of the eye. Swelling of the the junction between the optic nerve and the back of the eye is called papilloedema. An optician can confirm this.
The best treatment for Intracranial Hypertension is weight reduction, but often medication is used and procedures to reduce pressure like Lumbar Puncture, or CSF Shunts are needed if vision is threatened.
8. Headaches in someone with previous cancer diagnosis
People with a previous diagnosis of cancer need to have any new headache taken seriously, especially if the cancer diagnosis was relatively recent – within the previous 5 years. Any one with active cancer and a new headache will tests to rule out dangerous headaches.
The reason for this is that active cancer or cancer that has been dormant can spread to the brain tissue itself – called cerebral metastases, or to the lining of the brain – called Malignant Carcinomatous Meningitis.
Some types of cancer can also spread to the bones of the skull – bony metastases – the most likely cancers to be myeloma, breast, lung, prostate, kidney and melanoma. These can be very painful, yet very difficult to detect even when using scanning techniques like CT and MRI.
Not just headaches – there are focal symptoms as well
In cerebral metastases the headache is almost always accompanied by epileptic seizures, significant confusion or a severe neurological deficit like paralysis or blindness.
In Malignant Carcinomatous Meningitis there is often new deafness, new facial weakness or double vision but an initial brain scan looks normal. This is because the cancer is not present in large lumps but has coated the nerves on the surface of the brain – a Lumbar Puncture is needed to try and identify cancer cells.
Metastases to the skull bones can also be very difficult to diagnose as they can be difficult to detect when they appear just behind the eye (at the ‘orbital apex’), or in the sphenoid and temporal bone (at the ‘clivus’ or at the ‘petrous apex’).
Cancer related headache can feel like Tension-Type Headache. The difference is that a cancer related headache will be accompanied by a focal neurological symptom or sign, or will be getting progressively worse day by day or week by week. Tension-Type Headache does not have these features.
Most people with a previous cancer diagnosis who develop a new onset headache will not have a dangerous headache due to cancer spreading to the head. Most have a safe diagnosis of Tension-Type Headache or pain referred from the neck called Cervicogenic Headache.
9. New Onset Headaches in someone with known HIV Infection
HIV infection increases the risk of a low grade infection within the head which could present with a persistent new onset headache. Fever may or may not be present. HIV increases the risk of serious infection called cryptococcus Meningitis. A Brain Scan and Lumbar Puncture will confirm or rule out cryptococcus infection.
People with HIV Infection have an increased risk of Chronic Daily Headache without finding an underlying cause.
Someone with HIV may have a dangerous headache and requires careful investigation before making a diagnosis of Tension-Type Headache, Migraine or Cervicogenic Headache.
10. New Onset Headaches with loss of menstrual cycle / loss of libido
A new onset of headache accompanied with changes in menstrual function or sexual desire can indicate a problem with the pituitary gland. The pituitary gland is the main hormone control centre in the brain. Too much Growth Hormone, Prolactin or ACTH lead to headaches and changes in bodily function.
Growth Hormone changes facial appearance, makes gaps appear between teeth and increases the size and shape of hands and feet (Acromegaly).
Too much Prolactin makes breast milk to appear (Galactorrhoea) and reduces libido or makes the menstrual cycle irregular.
Lastly, too much ACTH causes high blood pressure that is very difficult to control.
The headache that accompanies pituitary tumours is a dull, persistent pain which can affect any part of the head.
The clue is not the quality of the pain, but the fact that it is new, persistent and accompanied by these changes in bodily function. These changes in bodily function can be very subtle – it is only on looking at old photographs that many people realise that they may be getting acromegaly for example.
Some people with pituitary gland headaches describe recurrent brief intense headaches that sound like Cluster Headache. These feel like dangerous headaches as they are so severe.
11. New Onset Headache with Scalp Tenderness and Weight Loss
This pattern of symptoms usually occurs in someone over the age of 50 years. The headache increases over several days to a week. Alongside the headache you lose appetite, weight or feel run down.
The scalp is sore and tender on one side of the head. Scalp arteries are difficult to feel – they no longer pulse and are tender to touch.
This combination of symptoms suggests Temporal Arteritis – also called Giant Cell Arteritis.
Arteritis is one of the dangerous headaches. It can cause permanent loss of vision in one or both eyes if left untreated. Early treatment with steroids reduces the risk of visual loss.
In Temporal Arteritis, the ESR Blood Test is high – greater than 50mm in an hour. A positive Temporal Artery Biopsy confirms the diagnosis.
There is no one feature of Temporal Arteritis headache that accurately distinguishes it from less dangerous headaches. The key feature is that it is a new onset pain in someone over the age of 50 years.
12. New Onset of Headache In Wintertime or after Electricity Black Out
This scenario is trying to make people remember that Carbon Monoxide Poisoning is a cause of new onset severe headaches.
Carbon Monoxide usually comes from poorly ventilated open fires, poorly ventilated central heating systems or from use of a diesel electricity generator.
This is why these dangerous headaches occur in cold weather or following a power cut. Warehouse workers who operate combustion-engine machinery can also be at risk. 80% of people with Carbon Monoxide Poisoning have a dull, generalised headache at the time of diagnosis.
This headache is exactly the same as Tension-Type Headache, although it may throb too. The clue to the diagnosis is the situation, not the symptom itself. The person has a completely new headache and is coming from a setting of Carbon Monoxide exposure.
Carbon Monoxide Poisoning might affect more than one family member or work colleague. If there is more than one person ill, do not make the mistake of thinking it’s an infection.
Removing the person from the source of the Carbon Monoxide Gas makes the headache stop. The headache returns when they are back to the Carbon Monoxide environment.
Carbon Monoxide Poisoning needs hospital assessment and treatment. The diagnosis is confirmed by a blood gas analysis.
Always think of this important environmental hazard as Carbon Monoxide Poisoning can kill.
13. A new diagnosis of Cluster Headache
Cluster Headache affects one-side of the head. It becomes very severe within a few minutes. Most often it is in or above one eye. During the attack the eye waters, your nose may either run or feel congested. The pain feels like severe pressure or a hot poker in the eye. It is almost impossible to describe the sensation – it feels so extreme.
On the affected side the eyelid may drop down and the white of the eye looks bloodshot. The pain is so severe that it feels like you belong to another world – your mind cannot think of anything else. It’s a dark and dangerous place.
The pain is so intense that you may feel driven to do the following: bang your head off a wall or think about trying to gouge out your eye. Sometimes you feel driven to do a repetitive destructive behaviour. Examples are banging fists on a table or chopping wood vigorously.
A Cluster Headache attack lasts about an hour.
This headache may return later that day or often appears during sleep. A person with Cluster Headache will then have similar bouts of headache every day for 4-6 weeks before they go away again.
Cluster Headache is seasonal in some people e.g. appears every autumn. Diagnosis can be delayed as by the time you see your doctor you look completely well. 75% of people with Cluster Headache have recurrent attacks.
An enlarged Pituitary Gland or a tear in the lining of the Carotid Artery – called Internal Carotid Artery Dissection can cause the same symptoms as Cluster Headache. This is why it is prudent to do an MRI Scan of Head in new onset Cluster Headache.
14. A New Diagnosis of Trigeminal Neuralgia
The Trigeminal Nerve is the main nerve that brings sensation from one side of the head and face. Sudden, short-lived pains is ‘Neuralgia’.
Trigeminal Neuralgia affects the lower half of face. You trigger Trigeminal Neuralgia by touching the face, chewing, talking, shaving, putting on make up or exposure to a breeze.
Most older people (older than 45 years) with Trigeminal Neuralgia do not have a serious cause for their symptoms.
In younger people (younger than 45 years) Trigeminal Neuralgia can a symptom of inflammation of the brain. Multiple Sclerosis is one of the treatable causes of brain inflammation.
If someone has Trigeminal Neuralgia affecting both sides of the face then this increases the chance that inflammation is present. Trigeminal Neuralgia can be caused by a meningioma or nerve sheath tumour affecting the Trigeminal Nerve.
An MRI Scan is a useful investigation for Trigeminal Neuralgia that is bilateral or occurs in younger people.
15. Severe Persistent Headache with a Body Mass Index greater than 40
People, usually women, with very high Body Mass Index are prone to High Intracranial Pressure. The headache of High Intracranial Pressure is usually a general severe headache that will not go away.
Unidentified High Pressure causes Visual Loss. Pulsatile tinnitus accompanies the pain of High Intracranial Pressure. Pulsatile Tinnitus is a whooshing noise in time to your pulse. If a Visual Field test is normal, the treatment is weight loss. An abnormal visual field test will require treatment such as drugs (acetazolamide), lumbar punctures or even shunt surgery.
16. Chronic Headaches that are Completely Out of Control
Chronic Daily Headache, like Chronic Migraine is one of the dangerous headaches. Not because life is at risk, but because they stop you living a fulfilling life.
About 20% of people who attend emergency rooms for headache management are in this category.
The most common pattern of headache is a background pain or pressure that never goes away. This usually involves the whole or top of the head, or feels like a squeezing band around the head. This daily discomfort is usually bearable.
However, every day or every few days the pain will increase and feel like Migraine. A severe, throbbing, sickening pain and light, noise, smell and movement are intensely unpleasant. You cannot function and have to take to bed or stop what you are doing.
You reach a point where you worry that there must be a dangerous cause for your headaches.
The diagnosis is usually Chronic Migraine if features of dangerous headaches are absent and your eye and neurological examination are normal.
Knowing this diagnosis is very important as it means that you are safe and that your pain does not mean you are in danger. Knowing you are safe is the first step towards getting in control of Chronic Migraine.
I have written an easy to follow guide on the best options for getting control of headaches. Before you start spending lots of money on expensive headache treatments or programmes you need to sort out your thinking, make sure you’ve avoided common mistakes with medicines and have considered drug-free treatments.
What to Do if You Suspect Dangerous Headaches?
You must see your own doctor if you suspect dangerous headaches. An ordinary clinical examination rules out almost all of these dangerous headaches. Your doctor will know if you need further investigation or specialist advice.
If your Headaches are Not Dangerous?
Then get started with your free online course to get you back in control.
Other useful pages for you:
Sharp Head Pains – what causes that?
Dangerous Headaches: References
Devenney, E., Neale, H., & Forbes, R. B. (2014). A systematic review of causes of sudden and severe headache (Thunderclap Headache). Journal of Headache & Pain, 15, 49. doi:10.1186/1129-2377-15-49
Forbes, R. B. (2014). Acute headache. Ulster Medical Journal, 83(1), 3-9.
The full list of 33 dangerous headaches references are here
Copyright 2016 of Forbes Neurology Services Ltd NI 608770 and Dr Raeburn Forbes
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