Centrally-acting non-opioid analgesic Pregnancy: No evidence of safety in human pregnancy and no evidence from animal work that it is free from hazard — avoid in pregnancy unless considered absolutely necessary by the physician. Excreted in human milk at concentrations similar to maternal plasma; breast-feeding should be discontinued during treatment.

Nefopam hydrochloride

Brand names: Acupan

Nefopam hydrochloride is a non-opioid, non-steroidal centrally acting analgesic used for moderate pain that has not responded to other non-opioid analgesics.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 30-90 mg (1-3 x 30 mg tablets) three times daily depending on response; recommended starting dose 30-60 mg (1-2 tablets) three times daily

Route: Oral

Frequency: Three times daily

Max: 90 mg (3 tablets) three times daily

Elderly: older patients may require a reduced dose because of slower metabolism — it is strongly recommended the starting dose does not exceed one 30 mg tablet three times daily, as older people appear more susceptible to CNS side effects and cases of hallucinations and confusion have been reported in this age group. Paediatric: safety and efficacy in children under 12 years has not been established and no dosage recommendation can be given for patients under 12 years — verify any paediatric use against a children's formulary. Not to be used in the treatment of myocardial infarction (no clinical experience in this indication). Hepatic and renal insufficiency may interfere with metabolism and excretion. Use with caution in angle-closure glaucoma and in patients with, or at risk of, urinary retention. May cause a temporary, harmless pink discolouration of the urine. Use may lead to drug dependence — prescribe with caution in patients with a history of substance use and/or mental health disorders and monitor for signs of dependence.

Dose adjustments

Renal

Patients with end stage renal disease may experience increased serum peak concentrations — it is recommended the daily dose be reduced.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

History of convulsive disorders
Patients taking monoamine oxidase (MAO) inhibitors
Known hypersensitivity to any of the excipients

Side effects

Nausea, dry mouth and gastrointestinal disturbance (including abdominal pain and diarrhoea)
Nervousness, confusion, hallucination
Light-headedness, dizziness, paraesthesia, tremor, convulsions
Urinary retention
Hypotension, syncope, palpitations
Angioedema and allergic reactions; rarely drug dependence

Interactions

Tricyclic antidepressants — caution when given concurrently
Other agents with anticholinergic or sympathomimetic activity — side effects may be additive
May interfere with screening tests for benzodiazepines and opioids, giving false positive results

Clinical monograph

How it works

It is thought to act centrally by inhibiting reuptake of serotonin, noradrenaline and dopamine, producing analgesia without the typical opioid or anti-inflammatory mechanisms.

Prescribing in practice

It has antimuscarinic and sympathomimetic effects, so avoid in convulsive disorders and use with caution in those with cardiovascular disease, urinary retention or angle-closure glaucoma risk.
Avoid concurrent use with monoamine oxidase inhibitors and use cautiously with other serotonergic or anticholinergic drugs.
It may colour the urine pink, which is harmless but can alarm patients.

Monitoring

Monitor analgesic response and for antimuscarinic and sympathomimetic adverse effects such as dry mouth, tachycardia, urinary difficulty and CNS stimulation.

Counselling the patient

Your urine may turn pink; this is harmless.
Report palpitations, difficulty passing urine, marked dizziness or a dry mouth that troubles you.

Evidence & guidelines

Use is informed by the product SPC; nefopam offers a non-opioid option for moderate pain in established analgesic practice.

Reference: Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways