Post-herpetic neuralgia is lasting nerve pain in an area previously affected by shingles.
It's estimated that up to one in five people with shingles will get post-herpetic neuralgia. Older people are particularly at risk.
Many people with post-herpetic neuralgia make a full recovery within a year. But symptoms occasionally last for several years or may be permanent.
Symptoms of post-herpetic neuralgia
The main symptom of post-herpetic neuralgia is intermittent or continuous nerve pain in an area previously affected by shingles.
The pain has been described as burning, stabbing, shooting, aching, throbbing or like electric shocks.
The affected area may also:
feel intensely itchy
be more sensitive to pain than usual
feel painful as a result of something that wouldn't normally hurt, such as a light touch or cool breeze
When to see your GP
See your GP if you have ongoing pain after having shingles. They can advise you about treatment options, including medicines you can only get on prescription.
Treatments for post-herpetic neuralgia
Medication can ease the symptoms of post-herpetic neuralgia, although it may not relieve the pain completely.
Widely available painkillers, such as paracetamol and ibuprofen, don't usually help, so your doctor may prescribe a different type of painkiller.
Some medicines used to treat depression also work for nerve pain and are sometimes used for post-herpetic neuralgia.
Causes of post-herpetic neuralgia
In post-herpetic neuralgia, the virus causes inflammation of the nerves under the skin of the affected area. Neuralgia is a medical term for pain resulting from nerve inflammation or damage.
It's not clear why some people with shingles develop post-herpetic neuralgia, but increasing age, pain during the early stage of shingles and severe pain throughout an episode of shingles are all associated with an increased risk of the condition.
Preventing post-herpetic neuralgia
There's no definite way to prevent post-herpetic neuralgia. But if shingles is treated early with antiviral medication, the risk of complications such as post-herpetic neuralgia is reduced.
If you develop symptoms such as pain or a rash that suggests shingles, see your GP as soon as possible to discuss taking an antiviral medication.
Having the shingles vaccination will help you avoid getting the infection in the first place. If you've had shingles before, the vaccine will also reduce your risk of getting it again. It's available on the NHS to some people in their 70s.
Treatment - Post-herpetic neuralgia
There are some things you can do yourself to try to reduce the discomfort of post-herpetic neuralgia. Medication can also be used to help relieve the pain.
Self-help
To help reduce the pain and irritation of post-herpetic neuralgia:
wear comfortable clothing – cotton or silk clothing usually causes less irritation
use cold packs – some people find cooling the affected area withanice pack helps
Creams and plasters
Your GP can prescribe treatments that you apply directly to the painful area.
Lidocaine plasters
Lidocaine plasters are sticking plasters that contain a local anaesthetic. They can be useful when pain affects sleeping or daytime activity. They can't be used for more than 12 hours at a time.
Capsaicin cream
Capsaicin is the substance that makes chilli peppers hot. It's thought to work for nerve pain by stopping the nerves sending pain messages to the brain.
Your GP can prescribe capsaicin as a low-dose cream. You apply it to the affected area a few times a day, but only when the rash has healed. It works by changing the way the nerve endings function.
High-strength capsaicin patches can also be used to treat post-herpetic neuralgia. They're available at specialist pain clinics and are applied as a single treatment in the clinic or at hospital. If effective, the treatment can be repeated, usually every few months depending on how your symptoms have improved.
Medication
Medication may not stop the pain completely, but it can help reduce it. You may need to try a number of different types of medicine to find the one, or combination, that works best for you.
Commonly used painkillers don't work for post-herpetic neuralgia. But your GP may suggest using paracetamol or a combination of paracetamol and codeine initially to see if it has an effect.
Some medicines used to treat depression also work for nerve pain, so you may be advised to try one of these.
Antidepressants
Amitriptyline and duloxetine are the two main antidepressants prescribed for post-herpetic neuralgia.
You'll usually be started on a low dose, which may be increased depending on the benefits and side effects. It may take a few weeks to feel the full effects.
Common side effects include a dry mouth, constipation, dizziness and drowsiness. Not everyone gets side effects.
If these medications still don't help after several weeks, or if they're causing significant side effects, your dose will need to be gradually reduced to prevent withdrawal effects.
Anticonvulsants
Gabapentin and pregabalin are the two main anticonvulsants prescribed for post-herpetic neuralgia.
Like the antidepressants used for post-herpetic neuralgia, they should be started at a low dose, which is gradually increased over a few days or weeks. They also usually need to be taken for a few weeks before they start to take effect.
Not everyone gets side effects when taking gabapentin and pregabalin. Possible side effects can include dizziness, drowsiness, poor memory, increased appetite and weight gain.
If these medications still don't help after several weeks, or if they're causing significant side effects, your dose will need to be gradually reduced.
Other treatments
If your pain gets worse despite treatment, you may be referred to a specialist pain clinic. While waiting for your appointment, you might be offered a medication called tramadol.
Tramadol can be addictive if taken for long periods, so it should be prescribed for the shortest time possible and stopped if it doesn't help.
If other medications haven't helped, stronger painkillers, such as morphine-based medications, may be recommended. These can be started by a GP but may need to be reviewed by a pain specialist. If these medications don't help, they should be stopped.
The National Institute for Health and Care Excellence (NICE) has a list of questions about medications used to treat neuropathic pain that you may want to ask your pain specialist.
Living with post-herpetic neuralgia
Living with post-herpetic neuralgia can be very difficult because it can affect your ability to carry out simple daily activities, such as dressing and bathing. It can also lead to further problems, including extreme tiredness, sleeping difficulties and depression.
The British Pain Society, Pain Concern and Pain UK
can also provide further help and support.
can also provide further help and support.
Source: NHS Choices