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Tricyclic Antidepressant / Neuropathic Pain Agent

Amitriptyline (Neuropathic Pain / Migraine)

Brand names: Tryptizol

Used in: Headache & Migraine

Amitriptyline is a tricyclic antidepressant used, at lower doses than for depression, for neuropathic pain and migraine prophylaxis.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

US labelling (FDA)

Reference — US labelling, may differ from UK

DOSAGE AND ADMINISTRATION Oral Dosage Dosage should be initiated at a low level and increased gradually, noting carefully the clinical response and any evidence of intolerance. Initial Dosage for Adults For outpatients, 75 mg of amitriptyline hydrochloride a day in divided doses is usually satisfactory. If necessary, this may be increased to a total of 150 mg per day. Increases are made preferably in the late afternoon and/or bedtime doses. A sedative effect may be apparent before the antidepressant effect is noted, but an adequate therapeutic effect may take as long as 30 days to develop. An alternate method of initiating therapy in outpatients is to begin with 50 to 100 mg amitriptyline …

Source: US FDA prescribing information (openFDA / DailyMed), label dated 2024-06-12. Accessed 2026-06-12. US dosing and indications can differ from UK practice — use UK sources for prescribing decisions.

Clinical monograph

How it works

It inhibits the reuptake of noradrenaline and serotonin, modulating descending pain pathways; its analgesic effect in neuropathic pain is independent of any antidepressant action.

Prescribing in practice

  • Tricyclics are dangerous and cardiotoxic in overdose; prescribe with caution and consider the quantity supplied in patients at risk.
  • Anticholinergic effects (dry mouth, constipation, urinary retention, blurred vision), sedation and postural hypotension are common; use with caution in the elderly.
  • Use with caution in cardiovascular disease; sedation may impair driving and skilled tasks.

Monitoring

Review analgesic benefit against anticholinergic and sedative burden, particularly in older patients. Monitor blood pressure for postural drops and assess cardiovascular status before and during treatment where relevant.

Counselling the patient

  • Take it in the evening, as it can make you drowsy; this often improves after the first few weeks.
  • Do not drive or operate machinery until you know how it affects you.
  • Do not stop taking it suddenly; your dose should be reduced gradually.

Evidence & guidelines

Guideline-recommended for neuropathic pain (NICE CG173) and migraine prophylaxis (NICE CG150).

Reference: NICE NG193 Neuropathic Pain; NICE NG150 Migraine; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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