Neuropathic pain - drug treatment
Exam Tips
- In UK exams, define neuropathic pain as pain from somatosensory system lesion/disease and then immediately give classic descriptors: burning, electric-shock, allodynia, hyperalgesia.
- State NICE-concordant first-line choices for adults (excluding trigeminal neuralgia/sciatica): amitriptyline, duloxetine, gabapentin, or pregabalin, with single-agent therapy and careful titration.
- Mention dependence counselling and monitoring before/while prescribing gabapentin or pregabalin; include withdrawal risk if abruptly stopped.
- Always add safety: start low, frequent review, avoid routine dose escalation, and taper gradually when stopping.
- When presenting management in OSCEs, include functional goals (sleep, activity, mood) and non-pharmacological support, not drugs alone.
- Use a quick pain-pathway sketch (peripheral nerve -> dorsal horn sensitisation -> spinothalamic tract) if asked for mechanism; see Figure from your core neuroanatomy pain pathway notes.
Definition
Neuropathic pain is pain caused by a lesion or disease of the somatosensory nervous system, rather than ongoing tissue injury alone. It can arise from peripheral nerve pathology (for example diabetic polyneuropathy, post-herpetic neuralgia, nerve trauma, chemotherapy-induced neuropathy) or central lesions (for example stroke, spinal cord injury, multiple sclerosis). The pain may be spontaneous or stimulus-evoked and is typically persistent, with major effects on sleep, mood, and function.
Pathophysiology
Damage to peripheral or central somatosensory pathways causes ectopic impulse generation, abnormal sodium/calcium channel activity, reduced inhibitory interneuron function, and central sensitisation in dorsal horn and supraspinal circuits. This produces amplified pain signalling (hyperalgesia), pain to normally non-painful stimuli (allodynia), and sensory gain/loss phenomena. Descending inhibitory pathway dysfunction (noradrenergic/serotonergic) and neuroinflammation help explain why SNRIs, TCAs, and gabapentinoids can reduce symptoms but rarely cure the condition. See Figure from standard neuroanatomy pain-pathway diagrams (spinothalamic tract and dorsal horn sensitisation).
Risk Factors
- Diabetes mellitus (painful diabetic neuropathy)
- Herpes zoster (risk of post-herpetic neuralgia)
- Nerve injury after surgery or trauma
- Chemotherapy exposure (for example platinum agents, taxanes, vinca alkaloids)
- Spinal pathology causing radicular neuropathic pain
- Stroke, multiple sclerosis, or spinal cord injury
- Tumour infiltration or compression of nerves
- Older age and polypharmacy (higher adverse-effect burden)
Clinical Features
Symptoms
- Burning, shooting, stabbing, or electric-shock-like pain
- Tingling, prickling, tightness, numbness, or itching dysaesthesia
- Spontaneous pain or pain provoked by light touch/cold
- Sleep disturbance, fatigue, low mood, reduced daily participation
- Pain may be constant or intermittent
Signs
- Allodynia on light brush or pressure testing
- Hyperalgesia to pinprick
- Sensory loss in a neuroanatomical distribution
- Sensory gain phenomena (dysaesthesia/paraesthesia)
- Occasionally anaesthesia dolorosa
Investigations
Management
Lifestyle Modifications
- Give clear verbal and written education on diagnosis, realistic goals, and slow onset of benefit
- Set shared functional targets (sleep, mobility, daily activity), not pain score alone
- Use pacing, graded activity/physiotherapy, and psychological support (for example CBT-based pain coping)
- Address sleep hygiene and mood comorbidity
- Discuss medicine safety, storage, overdose risk, withdrawal symptoms, and who to contact if problems occur
Pharmacological Treatment
Tricyclic antidepressant (first-line option)
- Amitriptyline 10-25 mg at night initially; increase by 10-25 mg every 3-7 days to effective/tolerated dose, usually max 75 mg/day in primary care
Trial for 6-8 weeks with at least 2 weeks at maximum tolerated dose before judging failure. Avoid abrupt stopping; taper over at least 4 weeks to reduce discontinuation symptoms. Use caution in older adults due to anticholinergic effects, sedation, falls risk, and cardiotoxicity in overdose; avoid with recent MI, significant arrhythmia risk, or severe liver disease.
SNRI (first-line option)
- Duloxetine 30 mg once daily initially, then 60 mg once daily; can increase to max 120 mg/day if needed and tolerated
Useful if comorbid depression/anxiety. Contraindicated with MAOIs, severe hepatic impairment, and severe renal impairment (CrCl <30 mL/min). Monitor for hypertension, nausea, insomnia, serotonin syndrome risk with other serotonergic drugs, and withdrawal if stopped suddenly.
Gabapentinoid (first-line option)
- Gabapentin 300 mg once daily day 1, 300 mg twice daily day 2, 300 mg three times daily day 3; then titrate to 900-3600 mg/day in 3 divided doses
Assess risk of misuse/dependence before prescribing; counsel on withdrawal if doses missed or stopped abruptly. Adjust dose in renal impairment. Adverse effects include dizziness, somnolence, gait instability, and respiratory depression risk when combined with opioids/CNS depressants.
Gabapentinoid (first-line option)
- Pregabalin 150 mg/day in 2-3 divided doses initially; increase after 3-7 days to 300 mg/day; if needed up to 600 mg/day
Controlled drug (Schedule 3): dependence and diversion risks require monitoring and limited quantities where appropriate. Renal dose adjustment required. Warn about sedation, blurred vision, weight gain, peripheral oedema, and withdrawal symptoms on abrupt cessation.
Prescribing strategy and safety principles
- Use ONE neuropathic pain medicine at a time (do not routinely co-prescribe amitriptyline, duloxetine, gabapentin, and pregabalin together)
Start low, titrate gradually, and review regularly to balance benefit versus harm. If ineffective or not tolerated, switch to an alternative first-line agent with planned taper/cross-over. Avoid automatic long-term dose escalation once an effective dose is established. In pregnancy or pregnancy planning, seek specialist advice due to fetal safety considerations.
Surgical / Interventional
- Consider specialist pain referral for refractory neuropathic pain (for example neuromodulation such as spinal cord stimulation in selected cases)
- Treat structural causes when present (for example decompression for compressive radiculopathy) via specialist pathways
Complications
- Chronic sleep disturbance and fatigue
- Anxiety, depression, and reduced quality of life
- Functional decline, work disability, and social withdrawal
- Adverse drug effects (sedation, falls, anticholinergic burden, serotonin toxicity, overdose)
- Dependence/misuse and withdrawal syndromes, especially with gabapentinoids
Prognosis
Neuropathic pain is often persistent and difficult to fully reverse because the underlying neural lesion may be permanent. In routine practice, only a proportion of patients achieve partial relief (commonly around 40-60%), so long-term management usually focuses on improving function, sleep, and quality of life while minimising treatment harms.
Sources & References
💊BNF Drug References(3)
- Capsaicin[management.pharmacological]
- Ephedrine hydrochloride[management.pharmacological]
- Nortriptyline[management.pharmacological]
✅NICE Guidelines(1)
- Neuropathic pain - drug treatment[overview]
📖Textbook References(20)
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 978)[context]
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 977, 978)[context]
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 1782)[context]
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 1008)[context]
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 952)[context]
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 961)[context]
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 952)[context]
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 951, 952)[context]
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 977, 978)[context]
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 977, 978)[context]
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 1121)[context]
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 1271)[context]
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 1431, 1432)[context]
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 1838)[context]
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 1432)[context]
- David Randall PhD MRCP (Editor), John Booth PhD MRCP (Editor), K - Kumar and Clark's Clinical Medicine (2025, American Elsevier Publishing Co.) - libgen.li.pdf(pp. 1008)[context]
- [Oxford Medical Handbooks] Ian Wilkinson, Tim Raine, Kate Wiles, Anna Goodhart, Catriona Ha - Oxford Handbook of Clinical Medicine (2017, Oxford University Press) - libgen.li.pdf(pp. 519, 520)[context]
- [Oxford Medical Handbooks] Ian Wilkinson, Tim Raine, Kate Wiles, Anna Goodhart, Catriona Ha - Oxford Handbook of Clinical Medicine (2017, Oxford University Press) - libgen.li.pdf(pp. 548)[context]
- [Oxford Medical Handbooks] Ian Wilkinson, Tim Raine, Kate Wiles, Anna Goodhart, Catriona Ha - Oxford Handbook of Clinical Medicine (2017, Oxford University Press) - libgen.li.pdf(pp. 80)[context]
- [Williams, Bailey and Love's Short Practice of Surgery] Norman Williams, Christopher Bulstrode, P Ronan O'Connell - Bailey & Love's Short Practice of Surgery 26E (2013, CRC Press) - libgen.li.pdf(pp. 636, 637)[context]