Trigeminal neuralgia: symptoms, causes and treatment

The NHS explains that ordinary painkillers such as paracetamol are not effective for trigeminal neuralgia, so an anticonvulsant is usually prescribed. Carbamazepine, the first-choice medicine, slows electrical impulses in the nerves and reduces their ability to send pain messages. It 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.

It is taken regularly rather than only during attacks, started at a low dose once or twice a day and increased gradually, up to 4 times a day, until pain relief is satisfactory. The NHS stresses that taking too much too soon, or stopping too quickly, can cause serious problems, so changes must follow medical advice. Side effects include tiredness, dizziness, difficulty concentrating, unsteadiness, sickness, double vision, a reduced number of infection-fighting white blood cells and allergic skin reactions.

The NHS gives important safety points. A severe skin rash with flushing, blisters or ulcers needs a 999 call or A&E because carbamazepine has been linked to Stevens-Johnson syndrome. Thoughts of self-harm also need a 999 call or A&E. Carbamazepine has been linked to an increased risk of problems for a baby if taken in pregnancy, so tell your GP at once if you become pregnant.

If carbamazepine stops working or causes troublesome side effects you should be referred to a specialist. Other medicines that have been used include oxcarbazepine, lamotrigine, gabapentin, pregabalin and baclofen; none is specifically licensed for trigeminal neuralgia, and specialists should tell you when a medicine is unlicensed and discuss risks and benefits.

When medicine does not control symptoms, or side effects are too troublesome, specialists such as neurologists with a headache interest, neurosurgeons and pain medicine specialists may discuss procedures. The NHS says there is no guarantee any will work, and that if one fails you can try another or continue medicines.

Percutaneous procedures pass a needle or thin tube through the cheek to the nerve under X-ray guidance, with heavy sedation or general anaesthetic. They include glycerol injection, radiofrequency lesioning and balloon compression. They work by deliberately injuring the nerve, and the NHS says relief usually lasts a few years or sometimes only months. The main side effect is facial numbness, which can be permanent, and very rarely a combination of numbness and continuous pain called anaesthesia dolorosa.

Stereotactic radiosurgery uses a concentrated beam of radiation, with no incision and no general anaesthetic. Pain relief can take weeks or months to appear and may last months or years; facial numbness and pins and needles are the most common complications. Microvascular decompression is a major operation under general anaesthetic that relieves pressure from blood vessels touching the nerve without intentionally damaging it. The NHS says research suggests it offers the best results for long-term relief but carries risks including hearing loss, facial numbness and, very rarely, stroke.

The trigeminal nerve carries sensations of pain and touch from the face, teeth and mouth to the brain. In trigeminal neuralgia this nerve sends sudden, severe pain signals. The NHS describes the pain as sharp, shooting or like an electric shock in the jaw, teeth or gums, coming in short unpredictable attacks. In most cases only one side of the face is affected, usually the lower part, and very occasionally both sides, though not usually at the same time.

Attacks can come regularly for days, weeks or months. In severe cases the NHS says they may happen hundreds of times a day. The pain can improve or even disappear for months or years (remission), although these periods tend to get shorter over time, and some people go on to develop a more continuous aching, throbbing or burning sensation alongside the sharp attacks.

It is thought to be rare. NHS inform reports that estimates of new UK cases vary and that one commonly quoted figure is probably too high because the condition tends to be over-diagnosed. What is not in doubt is how disruptive it can be: the NHS lists weight loss, isolation and depression among the problems that can develop.

Attacks are typically brought on by activities that involve lightly touching the face, such as washing, eating and brushing the teeth. Wind, even a slight breeze or air conditioning, and movement of the face or head can also set one off. Sometimes pain happens without any trigger at all.

Because ordinary actions provoke the pain, people may stop eating properly, avoid talking or skip tooth brushing, which can lead to weight loss and dental problems. Keeping a simple note of what sets pain off, how long attacks last and which part of the face is affected gives your GP exactly the information the NHS says is used in diagnosis.

• Shaving, applying make-up and washing the face

• Chewing, drinking or brushing teeth

• A cold breeze or air conditioning on the cheek

• Turning the head quickly or speaking

The NHS says trigeminal neuralgia is usually caused by compression of the trigeminal nerve, most often by a nearby blood vessel pressing on part of the nerve inside the skull. It can also happen when the nerve is damaged by another condition such as multiple sclerosis (MS) or a tumour.

The NHS also notes that trigeminal neuralgia is very unlikely to be the first symptom of MS, and that MS may be a more likely cause if you have a family history or other features of that condition. A more common type of nerve pain that develops in an area previously affected by shingles is called post-herpetic neuralgia and is a separate diagnosis.

Because the pain is often felt in the jaw, teeth or gums, many people see a dentist first. The NHS says the dentist will look for common causes such as a dental infection or cracked tooth, and that if no obvious cause is found you should see a GP. There is no specific test for trigeminal neuralgia, so the diagnosis is usually based on your symptoms and the description of the pain.

The GP will ask how often attacks happen, how long they last and which areas of the face are affected, and may examine your head and jaw. Other conditions that can mimic it include jaw or dental problems, cluster headaches and post-herpetic neuralgia. An MRI scan is often used to help with diagnosis, to look for causes such as sinus inflammation, tumours on a facial nerve, MS-related nerve damage, and sometimes a blood vessel compressing the nerve.

The NHS says attacks can come regularly for days, weeks or months, and that the pain can improve or even disappear for months or years (remission). These periods tend to get shorter over time, and some people go on to develop a more continuous aching, throbbing or burning sensation alongside the sharp attacks.

The NHS says carbamazepine is usually continued for as long as necessary, which could be many years, unless pain becomes much better or disappears, and that stopping must be slow and guided by a doctor. The NHS describes it as usually a long-term condition.

The NHS says to call 999 or go to A&E if you are taking carbamazepine and develop a severe skin rash with flushing, blisters or ulcers, because it has been linked to Stevens-Johnson syndrome, or if you have thoughts of harming yourself.

See a GP for frequent or persistent facial pain, particularly if paracetamol and ibuprofen do not help and a dentist has ruled out dental causes. Seek urgent help for sudden weakness or loss of vision alongside facial pain.

See a GP for frequent or persistent facial pain, particularly if paracetamol and ibuprofen do not help and a dentist has ruled out dental causes. On the NHS your GP can start carbamazepine and refer you to neurology, neurosurgery or a pain clinic if treatment fails. Because the NHS says diagnosis can be difficult and slow, it is reasonable to ask for referral if pain keeps recurring.

Private neurologists, neurosurgeons and pain specialists can offer faster access to MRI and discussion of procedures. The decisions are the same in either setting: which procedure, what the chance of numbness is, how long relief is expected to last and what follow-up is arranged. Ask for the options to be explained in writing and for costs to be itemised. Seek urgent help via 999 or A&E for a severe skin rash with blistering, thoughts of self-harm, or sudden weakness or loss of vision alongside facial pain.