4.7.3 Neuropathic pain

Neuropathic pain (except trigeminal neuralgia*)

ChoiceDrugDosage
1st choice

Amitriptyline tablets 10mg, 25mg, 50mg; oral solution 10mg/5ml, 25mg/5ml, 50mg/5ml

Dose:
Initially 10–25 mg daily, as a single dose in the evening, then increased, if necessary according to response and tolerability, by 10–25 mg every 3–7 days; usual dose 25–75 mg daily,as a single dose in the evening; maximum dose 75 mg
2nd choice Gabapentin capsules 100mg, 300mg, 400mgDose:
300mg at night on day 1, 300mg twice daily on day 2 and then titrate up in steps of 300mg daily (total given in 3 divided doses) according to side effects/ response, to a usual max of 1.8g daily (note licensed max 3.6g daily but if no substantial improvement at 2.4g, increasing the dose further is unlikely to be of benefit)

Consider a lower starting dose of 100mg [unlicensed] if the patient is very frail or susceptible to sedative medications
3rd choiceDuloxetine capsules 30mg, 60mgDose:
60mg once daily, discontinue if inadequate response after 2 months; review treatment at least every 3 months; licensing allows maximum 60mg twice a day however there is no evidence that patients not responding to the initial recommended dose may benefit from dose up-titrations and the higher dose is associated with unwanted effects and therefore not recommended

A lower starting dose of 30mg once daily may be appropriate in some people
Nausea is common on initiation but may resolve on continued treatment

Localised neuropathic painAxsain 0.075% cream (capsaicin)Dose:
Apply 3-4 times a day, apply sparingly, not more often than every 4 hours

* Carbamazepine is first choice for trigeminal neuralgia*

Prescribing Notes 

  • See HSCB ‘Management of Non-Malignant Neuropathic Pain’
  • See NICE CG173 Neuropathic pain- pharmacological management
  • See NICE NG59 Low back pain and sciatica
  • Do not offer gabapentinoids, other antiepileptics, oral corticosteroids or benzodiazepines for managing sciatica as there is no overall evidence of benefit and there is evidence of harm (NICE NG59)
  • Use of validated tools e.g. DN4 or Leeds Assessment of Neuropathic Symptoms (LANSS) can help to identify neuropathic pain
  • Pregabalin and gabapentin can lead to dependence and may be misused or diverted. From 1st April 2019, gabapentin and pregabalin have been reclassified as schedule 3 controlled drugs – click here for further advice
  • Gabapentin tablets are more expensive than the capsules. When prescribing, use the most cost effective strength and formulation
  • Consider capsaicin cream 0.075% (Axsain®) for people with localised neuropathic pain who wish to avoid, or who cannot tolerate, oral treatments
  • Lidocaine medicated plasters are not recommended for routine use, they are only licensed in post-herpetic neuralgia and are listed on the HSC Deprescribing: Limited Evidence List and Stop List. An SOP for review of this product in primary care is available here.
  • Tapentadol should only be initiated on the recommendation of a specialist
  • If treatment, with regular assessment, is unsuccessful then referral for specialist advice is recommended

Cautions

  • Amitriptyline should be used with caution in the elderly and patients with glaucoma or prostatic hypertrophy. In the older patient, higher doses of amitriptyline are particularly likely to cause anticholinergic effects such as postural hypotension, sedation, confusion, dry mouth, urinary retention and constipation and should therefore be avoided. Gabapentin may be a safer option for neuropathic pain in these patients. Full details of amitriptyline cautions are available in the BNF
  • Caution on concurrent use of amitriptyline with other antidepressants or serotonerigic opiates (e.g. fentanyl, oxycodone, tapentadol, tramadol). When amitriptyline is co-prescribed with these agents a maximum daily dose of 10-20mg is recommended
  • In patients with a reduced eGFR, see BNF for dosing directions for initiating and titration of both gabapentin and pregabalin
  • Avoid co-prescribing CNS depressants e.g. benzodiazepines or gabapentinoids with opioids due to the increased risk of serious side effects e.g. respiratory depression
  • Duloxetine has been associated with an increase in blood pressure and cases of hypertensive crisis have been reported. BP monitoring is recommended in patients with known hypertension and/or other cardiac disease, especially during the first month of treatment.  Duloxetine is contraindicated in patients with uncontrolled hypertension. See SPC for further details