The main symptom of trigeminal neuralgia is sudden attacks of severe, sharp, shooting facial pain that last from a few seconds to about 2 minutes.

The pain is often described as excruciating, like an electric shock. The attacks can be so severe that you're unable to do anything while they're happening.

Trigeminal neuralgia usually affects one side of the face. In some cases it can affect both sides, although not usually at the same time.

The pain can be in the teeth, lower jaw, upper jaw or cheek. Less commonly the pain can also be in the forehead or eye.

You may sense when an attack is about to happen, although they usually start unexpectedly.

After the most severe pain has subsided you may experience a slight ache or burning feeling. You may also have a constant throbbing, aching or burning sensation between attacks.

You may experience regular episodes of pain for days, weeks or months at a time. Sometimes the pain may disappear completely and not return for several months or years. This is known as remission.

In severe cases of trigeminal neuralgia the attacks may happen hundreds of times a day and there may be no periods of remission.

Symptom triggers

Attacks of trigeminal neuralgia can be triggered by certain actions or movements, such as:

• talking
• smiling
• chewing
• brushing your teeth
• washing your face
• a light touch
• shaving or putting on make-up
• swallowing
• kissing
• a cool breeze or air conditioning
• head movements
• vibrations, such as walking or travelling in a car

However, pain can happen spontaneously with no trigger whatsoever.

Further problems

Living with trigeminal neuralgia can be very difficult and your quality of life can be significantly affected.

You may feel like avoiding activities such as washing, shaving or eating so you do not trigger the pain, and the fear of pain may mean you avoid social activities.

However, it's important to try to live a normal life and be aware that becoming undernourished or dehydrated can make the pain worse.

The emotional strain of living with repeated episodes of pain can lead to psychological problems, such as depression. During periods of extreme pain some people may even consider suicide. Even when pain-free, you may live in fear of the pain returning.

Read more advice about coping with chronic pain.

When to see a GP

You should see a GP if you experience frequent or persistent facial pain, particularly if standard painkillers such as paracetamol and ibuprofen do not help and a dentist has ruled out any dental causes.

Trigeminal neuralgia can be difficult to diagnose. The GP will try to identify the problem by asking about your symptoms and ruling out other conditions that could be responsible for your pain.

Read more about diagnosing trigeminal neuralgia.

The exact cause of trigeminal neuralgia is not known, but it's often thought to be caused by compression of the trigeminal nerve, or by another medical condition that affects this nerve.

The trigeminal nerve – also called the fifth cranial nerve – provides sensation to the face. You have one on each side.

Primary trigeminal neuralgia

Evidence suggests that in up to 95% of cases, trigeminal neuralgia is caused by pressure on the trigeminal nerve close to where it enters the brain stem, the lowest part of the brain that merges with the spinal cord.

This type of trigeminal neuralgia is known as primary trigeminal neuralgia.

In most cases the pressure is caused by an artery or vein squashing (compressing) the trigeminal nerve. These are normal blood vessels that happen to come into contact with the nerve at a particularly sensitive point.

It's not clear why this pressure can cause painful attacks in some people but not others, as not everyone with a compressed trigeminal nerve will experience pain.

It may be that, in some people, the pressure on the nerve wears away its protective outer layer (myelin sheath), which may cause pain signals to travel along the nerve. However, this does not fully explain why some people have periods without symptoms (remission), or why pain relief is immediate after a successful operation to move the blood vessels away from the nerve.

Secondary trigeminal neuralgia

Secondary trigeminal neuralgia is the term used when trigeminal neuralgia is caused by another medical condition or problem, including:

• a tumour
• a cyst – a fluid-filled sac
• arteriovenous malformation – an abnormal tangle of arteries and veins
• multiple sclerosis (MS) – a long-term condition that affects the nervous system
• facial injury
• damage caused by surgery including dental surgery

As the pain caused by trigeminal neuralgia is often felt in the jaw, teeth or gums, many people with the condition visit a dentist before going to a GP.

The dentist will ask you about your symptoms and give you a dental X-ray to help them investigate your facial pain. They'll look for common causes of facial pain, such as a dental infection or cracked tooth.

Trigeminal neuralgia is often diagnosed by a dentist, but if you have seen a dentist and they could not find an obvious cause of your pain, you should visit a GP.

Seeing a GP

There's no specific test for trigeminal neuralgia, so a diagnosis is usually based on your symptoms and description of the pain.

If you've experienced attacks of facial pain, the GP will ask you questions about your symptoms, such as:

• how often do the pain attacks happen
• how long do the pain attacks last
• which areas of your face are affected

The GP will consider other possible causes of your pain and may also examine your head and jaw to identify which parts are painful.

Ruling out other conditions

An important part of the process of diagnosing trigeminal neuralgia involves ruling out other conditions that cause facial pain.

By asking about your symptoms and carrying out an examination, the GP may be able to rule out other conditions, such as:

• migraine
• joint pain in the lower jaw
• giant cell arteritis (temporal arteritis) – where the medium and large arteries in the head and neck become inflamed and cause pain in the jaw and temples
• a possible nerve injury

The GP will also ask about your medical, personal and family history when trying to find the cause of your pain.

For example, you're less likely to have trigeminal neuralgia if you're under 40 years old. Multiple sclerosis (MS) may be a more likely cause if you have a family history of the condition or you have some other form of this condition.

However, trigeminal neuralgia is very unlikely to be the first symptom of MS.

MRI scans

If the GP is not sure about your diagnosis or you have unusual symptoms, they may refer you for an MRI scan of your head.

An MRI scan uses strong magnetic fields and radio waves to create detailed images of the inside of your body.

It can help identify potential causes of your facial pain, such as inflammation of the lining of the sinuses (sinusitis), tumours on one of the facial nerves, or nerve damage caused by MS.

An MRI scan may also be able to detect whether a blood vessel in your head is compressing one of the trigeminal nerves, which is thought to be the most common cause of trigeminal neuralgia.

A number of treatments can offer some relief from the pain caused by trigeminal neuralgia.

Identifying triggers and avoiding them can also help.

Most people with trigeminal neuralgia will be prescribed medicine to help control their pain, although surgery may be considered for the longer term in cases where medicine is ineffective or causes too many side effects.

Avoiding triggers

The painful attacks of trigeminal neuralgia can sometimes be brought on, or made worse, by certain triggers, so it may help to avoid these triggers if possible.

For example, if your pain is triggered by wind, it may help to wear a scarf wrapped around your face in windy weather. A transparent dome-shaped umbrella can also protect your face from the weather.

If your pain is triggered by a draught in a room, avoid sitting near open windows or the source of air conditioning.

Avoid hot, spicy or cold food or drink if these seem to trigger your pain. Using a straw to drink warm or cold drinks may also help prevent the liquid coming into contact with painful areas of your mouth.

It's important to eat nourishing meals, so consider eating mushy foods or liquidising your meals if you're having difficulty chewing.

Certain foods seem to trigger attacks in some people, so you may want to consider avoiding things such as caffeine, citrus fruits and bananas.

Medicine

As painkillers like paracetamol are not effective in treating trigeminal neuralgia, you'll usually be prescribed an anticonvulsant – a type of medicine used to treat epilepsy – to help control your pain.

Anticonvulsants were not originally designed to treat pain, but they can help to relieve nerve pain by slowing down electrical impulses in the nerves and reducing their ability to send pain messages.

They need to be taken regularly, not just when the pain attacks happen, but you can stop taking them if the episodes of pain cease and you're in remission. 

Unless a GP or specialist tells you to take your medicine in a different way, it's important to increase your dosage slowly. If the pain goes into remission, you can gradually reduce the dosage over the course of a few weeks. Taking too much too soon, or stopping the medicine too quickly can cause serious problems.

At the start, the GP will probably prescribe a type of anticonvulsant called carbamazepine, although a number of alternative anticonvulsants are available if this is ineffective or unsuitable.

Carbamazepine

The anticonvulsant carbamazepine is currently the only medicine licensed to treat trigeminal neuralgia in the UK. It can be very effective initially, but may become less effective over time.

You'll usually need to take carbamazepine at a low dose once or twice a day, with the dose being gradually increased and taken up to 4 times a day until it provides satisfactory pain relief.

Carbamazepine often causes side effects, which may make it difficult for some people to take.

These include:

• tiredness and sleepiness
• dizziness (lightheadedness)
• difficulty concentrating and memory problems
• confusion
• feeling unsteady on your feet
• feeling and being sick
• double vision
• a reduced number of infection-fighting white blood cells (leukopenia)
• allergic skin reactions, such as hives (urticaria)

You should speak to a GP if you experience any persistent or troublesome side effects while taking carbamazepine, particularly allergic skin reactions, as these could be dangerous.

Carbamazepine has also been linked to a number of less common but more serious side effects, including thoughts of self-harm or suicide.

Immediately report any suicidal feelings to a GP. If this is not possible, call NHS 111. 

Other medicines

Carbamazepine may stop working over time. In this case, or if you experience significant side effects while taking it, you should be referred to a specialist to consider alternative medicines or procedures.

There are a number of specialists you may be referred to for further treatment, including neurologists specialising in headaches, neurosurgeons, and pain medicine specialists.

In addition to carbamazepine, a number of other medicines have been used to treat trigeminal neuralgia, including:

• oxcarbazepine
• lamotrigine
• gabapentin
• pregabalin
• baclofen

None of these medicines are specifically licensed for the treatment of trigeminal neuralgia, which means they have not undergone rigorous clinical trials to determine whether they're effective and safe to treat the condition.

However, many specialists will prescribe an unlicensed medicine if they think it's likely to be effective and the benefits of treatment outweigh any associated risks.

If your specialist prescribes you an unlicensed medicine to treat trigeminal neuralgia, they should inform you that it's unlicensed and discuss the possible risks and benefits with you.

Read more about the licensing of medicines.

The side effects associated with most of these medicines can initially be quite difficult to cope with.

Not everyone experiences side effects, but if you do, try to persevere as they often diminish with time or at least until the next dosage increase.

Talk to a GP if you're finding the side effects very troublesome.

Surgery and procedures

If medicine does not adequately control your symptoms or is causing persistently troublesome side effects, you may be referred to a specialist to discuss the different surgical and non-surgical options available to you.

A number of procedures have been used to treat trigeminal neuralgia, so discuss the potential benefits and risks of each one with your specialist before you make a decision.

There's no guarantee that any of these procedures will work for you. However, if a procedure is successful, you will no longer need to take pain medicines unless the pain returns.

If one procedure does not work, you can try another procedure, or keep taking medicines for the short term or permanently.

Some of the procedures that can be used to treat trigeminal neuralgia are outlined below.

Percutaneous procedures

There are a number of procedures that can offer some relief from the pain of trigeminal neuralgia, at least temporarily, by inserting a needle or thin tube through the cheek and into the trigeminal nerve inside the skull.

These are known as percutaneous procedures. X-rays of your head and neck are taken to help guide the needle or tube into the correct place while you're heavily sedated with medicine or under a general anaesthetic, where you're unconscious.

Percutaneous procedures to treat trigeminal neuralgia include:

• glycerol injections – where a medicine called glycerol is injected around the Gasserian ganglion, where the 3 main branches of the trigeminal nerve join together
• radiofrequency lesioning – where a needle is used to apply heat directly to the Gasserian ganglion
• balloon compression – where a tiny balloon is passed along a thin tube that has been inserted through the cheek. The balloon is then inflated around the Gasserian ganglion to squeeze it; the balloon is then removed

These procedures work by deliberately injuring or damaging the trigeminal nerve, which is thought to disrupt the pain signals travelling along it. You're usually able to go home the same day.

Overall, these procedures are similarly effective in relieving trigeminal neuralgia pain, although there can be complications with each. These vary depending on the procedure and the individual.

The pain relief will usually only last a few years or, in some cases, a few months. Sometimes these procedures do not work at all.

The major side effect of these procedures is numbness in part or all of one side of the face, which can vary from being very numb or just pins and needles.

The sensation, which can be permanent, is often similar to the feeling you have after an injection at the dentist. You can also develop a combination of numbness and continuous pain called anaesthesia dolorosa, which is virtually untreatable, however this is very rare.

These procedures also carry a risk of other short- and long-term side effects and complications, including bleeding, facial bruising, eye problems and impaired hearing on the affected side. Very rarely, it can cause a stroke.

Stereotactic radiosurgery

Stereotactic radiosurgery is a fairly new treatment that uses a concentrated beam of radiation to deliberately damage the trigeminal nerve where it enters the brainstem.

Stereotactic radiosurgery does not require a general anaesthetic and no cuts (incisions) are made in your cheek.

A metal frame is attached to your head with 4 pins inserted around your scalp – a local anaesthetic is used to numb the areas where these are inserted.

Your head, including the frame, is held in a large machine for 1 to 2 hours while the radiation is given. The frame and pins are then removed, and you're able to go home after a short rest.

It can take a few weeks – or sometimes many months – to notice any change after stereotactic radiosurgery, but it can offer pain relief for some people for several months or years.

Facial numbness and pins and needles in the face are the most common complications associated with stereotactic radiosurgery. These side effects can be permanent and, in some cases, very troublesome.

Microvascular decompression

Microvascular decompression (MVD) is an operation that can help relieve trigeminal neuralgia pain without intentionally damaging the trigeminal nerve.

The procedure relieves the pressure placed on the trigeminal nerve by blood vessels that are touching the nerve or are wrapped around it.

MVD is a major procedure that involves opening the skull, and is carried out under general anaesthetic by a neurosurgeon.

A surgeon makes an incision in your scalp, behind your ear, and removes a small piece of skull bone. They then separate the blood vessel(s) from the trigeminal nerve using an artificial pad or a sling constructed from adjoining tissue.

Many people find this surgery is effective at easing or completely stopping the pain of trigeminal neuralgia.

It provides the longest lasting relief, with some studies suggesting that pain returns in about 3 out of 10 cases within 10 to 20 years of surgery.

Currently, MVD is the closest possible cure for trigeminal neuralgia. However, it's an invasive procedure and carries a risk of potentially serious complications, such as facial numbness, hearing loss, stroke and even death in around 1 in every 200 cases.

Further information and support

Living with a long-term and painful condition, such as trigeminal neuralgia, can be very difficult.

You may find it useful to contact a local or national support group, such as the Trigeminal Neuralgia Association UK, for more information and advice about living with the condition, and to get in touch with other people who have the condition to talk to them about their experiences.

A number of research projects are running both in the UK and abroad to find the cause of trigeminal neuralgia and develop new treatments and new medicines, so there's hope for the future.