neuropathic pain

Last edited 07/2019 and last reviewed 04/2021

Neuropathic pain is caused by inappropriate firing of pain-mediating nerve fibres.

Neuropathic pain has a heterogeneity of aetiologies, symptoms and underlying mechanisms

• often uncertainty regarding the nature and exact location of a lesion or health condition associated with neuropathic pain, particularly in non-specialist settings
  • examples of common conditions that have peripheral neuropathic pain as a symptom are painful diabetic neuropathy, post-herpetic neuralgia, trigeminal neuralgia, radicular pain, post-surgical chronic neuropathic pain, and neuropathic cancer pain (such as, chemotherapy-induced neuropathy, neuropathy secondary to tumour antigens, or caused by direct invasion or compression of neural structures)
    
    
  • examples of conditions that can cause central neuropathic pain include stroke, spinal cord injury and multiple sclerosis

Neuropathic pain can be intermittent or constant, and spontaneous or provoked

The patient may suffer chronic discomfort, often described as:

• burning
• shooting
• like an electric shock
• stabbing

In addition the patient may perceive:

• innocuous stimuli, such as light touch, as painful: this is allodynia
• mild discomfort as severe pain: this is hyperalgesia
• short discomfort as a prolonged severe pain: this is hyperpathia

Notes (1):

• MHRA advice on pregabalin and gabapentin:
  • as of 1 April 2019, because of a risk of abuse and dependence pregabalin and gabapentin are controlled under the Misuse of Drugs Act 1971 as class C substances and scheduled under the Misuse of Drugs Regulations 2001 as schedule 3
• MHRA advice on valproate:
  • valproate must not be used in pregnancy, and only used in girls and women when there is no alternative and a pregnancy prevention plan is in place. This is because of the risk of malformations and developmental abnormalities in the baby

Reference:

• NICE (July 2019). Neuropathic pain in adults: pharmacological management in nonspecialist settings