(ĐTĐ) – Neuropathic pain (‘neuralgia’) is a pain that comes from problems with signals from the nerves. There are various causes. It is different to the common type of pain that is due to an injury, burn, pressure, etc. Traditional painkillers such as paracetamol, anti-inflammatories, codeine and morphine may help, but often do not help very much. However, neuropathic pain is often eased by antidepressant or anti-epileptic medicines – by an action that is separate to their action on depression and epilepsy. Other pain relieving techniques are sometimes used.
What is neuropathic pain?
Pain is broadly divided into two types – nociceptive pain and neuropathic pain.
This is the type of pain that all people have had at some point. It is caused by actual, or potential damage to tissues. For example, a cut, a burn, an injury, pressure or force from outside the body, or pressure from inside the body (for example, from a tumour) can all cause nociceptive pain. The reason we feel pain in these situations is because tiny nerve endings become activated or damaged by the injury, and this sends pain messages to the brain via nerves.
Nociceptive pain tends to be sharp or aching. It also tends to be eased well by ‘traditional’ painkillers such as paracetamol, anti-inflammatory painkillers, codeine and morphine.
This type of pain is caused by a problem with one or more nerves themselves. There is often no ‘injury’ or tissue damage that triggers the pain. However, the function of the nerve is affected in a way that it sends pain messages to the brain. Neuropathic pain is often described as burning, stabbing, shooting, aching, or like an ‘electric-shock’.
Neuropathic pain is less likely than nociceptive pain to be helped by traditional painkillers. However, other types of medicines often work well to ease the pain (see below).
The rest of this leaflet is just about neuropathic pain.
What causes neuropathic pain?
Various conditions can affect nerves and may cause neuropathic pain as one of the features of the condition. These include the following:
Post herpetic neuralgia (pain following shingles)
Diabetic neuropathy – a nerve disorder that develops in some people with diabetes
Phantom limb pain following an amputation
Pain following chemotherapy
Atypical facial pain
Various other uncommon nerve disorders
Note: you can have nociceptive pain and neuropathic pain at the same time, sometimes caused by the same condition. For example, you may develop nociceptive pain and neuropathic pain from certain cancers.
More about the nature of neuropathic pain
Related to the pain there may also be:
Allodynia. This means that the pain comes on, or gets worse, with a touch or stimulus that would not normally cause pain. For example, a slight touch on the face may trigger pain if you have trigeminal neuralgia, or the pressure of the bedclothes may trigger pain if you have diabetic neuropathy.
Hyperalgesia. This means that you get severe pain from a stimulus or touch that would normally cause only slight discomfort. For example, a mild prod on the painful area may cause intense pain.
Paresthesia. This means that you get unpleasant or painful feelings even when there is nothing touching you, and no stimulus. For example, you may have painful pins and needles, or electric shock like sensations.
In addition to the pain itself, the impact that the pain has on your life may be just as important. For example, the pain may lead to disturbed sleep, anxiety and depression.
How common is neuropathic pain?
It is estimated that about 1 in 100 people in the UK have persistent (chronic) neuropathic pain. It is much more common in older people who are more prone to developing the conditions listed above.
What is the treatment for neuropathic pain?
Treating the underlying cause – if possible
Treating the underlying cause
If this is possible, it may help to ease the pain. For example, if you have diabetic neuropathy then good control of the diabetes may help to ease the condition. If you have cancer, if this can be treated then this may ease the pain. Note: the severity of the pain often does not correspond with the seriousness of the underlying condition. For example, postherpetic neuralgia (pain after shingles) can cause a severe pain, even though there is no rash or signs of infection remaining.