Management of neuropathic pain

Non-pharacological measures include:

• counselling and information
• TENS (transcutaneous electrical nerve stimulation)
• PENS (percutaneous electrical nerve stimulation)
  • TENS is a non-invasive therapeutic option, generally used to relieve pain, which uses peripheral nerve electrical stimulation by means of electrodes placed on the skin surface at known well-tolerated intensities
  • PENS, on the other hand, uses needle-like electrodes, similar to those used in acupuncture which are 1-4 cm long, located in soft tissues or muscles at the corresponding dermatomes for that local pathology
• acupuncture

The main pharmacological interventions for the management of neuropathic pain are:

• non-opiod analgesics and NSAIDS
• tricyclic antidepressants
• anti-epileptics
• capsaicin
• opioid analgesics
• serotonin-norepinephrine reuptake inhibitors (SNRIs) e.g. duloxetine, venlafaxine
• NMDA receptor antagonists such as ketamine

NICE guidance suggests

• for all neuropathic pain (except trigeminal neuralgia)
  • a choice of amitriptyline, duloxetine, gabapentin or pregabalin should be offered as initial treatment for neuropathic pain (except trigeminal neuralgia) (1)
    • from previous guidance there is some advice about titration (2)
      • for amitriptyline
        • start at 10 mg per day, with gradual upward titration to an effective dose or the person's maximum tolerated dose of no higher than 75 mg per day (higher doses could be considered in consultation with a specialist pain service)
      • for pregabalin
        • start at 150 mg per day (divided into two doses; a lower starting dose may be appropriate for some people), with upward titration to an effective dose or the person's maximum tolerated dose of no higher than 600 mg per day (divided into two doses)
          
          
  • if the initial treatment is not effective or is not tolerated, offer one of the remaining 3 drugs, and consider switching again if the second and third drugs tried are also not effective or not tolerated
    
    
  • tramadol should only be considered if acute rescue therapy (short-term use only) is needed
    • from previous guidance (2)
      • for tramadol as monotherapy, start at 50 to 100 mg not more often than every 4 hours, with upward titration if required to an effective dose or the person's maximum tolerated dose of no higher than 400 mg per day. If tramadol is used as combination therapy, more conservative titration may be required
        
        
  • capsaicin cream should be considered people with localised neuropathic pain who wish to avoid, or who cannot tolerate, oral treatments
    
    

Notes:

• when withdrawing or switching treatment, taper the withdrawal regimen to take account of dosage and any discontinuation symptoms (1)
• MHRA advice on valproate: In April 2018, we added warnings that 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 (1)
  
  
• 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 (as of 1 April 2019) (1)
  
  
• a meta-analysis revealed that, in patients with neuropathic pain, there is no statistically significant difference in clinical response rates between tricyclic antidepressants, anticonvulsants and serotonin-norepinephrine reuptake inhibitors (SNRIs) (3)
  • a review concluded that ".... Because the evidence to support the use of treatments for neuropathic pain is generally limited, treatment should be tailored to the individual's circumstances, taking into account any contraindications, co-morbidities etc. It is difficult to predict how a person will respond and trials of several drugs may be necessary to obtain optimal pain relief and minimise adverse effects. However, tricyclic antidepressants are a good first choice treatment for neuropathic pain and they are likely to be more cost-effective than SNRIs or anticonvulsants.." (3)

Reference:

• 1. NICE (July 2019). Neuropathic pain (adults) - pharmacological management (non-specialist settings)
• 2 NICE (March 2010). Neuropathic pain (adults) - pharmacological management (non-specialist settings)
• 3. Canadian Agency for Drugs and Technologies in Health. Anticonvulsants, serotonin-norepinephrine reuptake inhibitors, and tricyclic antidepressants in management of neuropathic pain: A meta-analysis and economic evaluation. Technology Report 116. December 2008
• 3. MeReC Monthly No.12 March 2009.