Nefopam is a centrally-acting non-opioid analgesic, which has no effect on bleeding time and platelet aggregation.
- nefopam, a benzoxazocine substance, is structurally related to orphenadrine and dyphehydramine (1)
- nefopam is neither a non-steroidal anti-inflammatory drug nor an opiate
- the mechanisms of analgesic action of nefopam are not well understood, they are similar to those of triple neurotransmitter (serotonin, norepinephrine, and dopamine) reuptake inhibitors and anticonvulsants (2)
- nefopam has been used mainly as an analgesic drug for nociceptive pain, as well as a treatment for the prevention of postoperative shivering and hiccups
- nefopam is not associated with respiratory inhibition
- a review stated (3):
- nefopam appears no more potent than non-steroidal anti-inflammatory drugs (NSAIDs), but is commonly associated with adverse drug reactions and is toxic in overdose
- nefopam may sometimes be preferred when alternatives are contraindicated or ineffective, or used as add-on therapy when pain is inadequately controlled.
- prescribers should carefully consider whether the potential benefits outweigh the risks of adverse effects in individual patients
- treatment should be reviewed regularly and stopped if benefits are not seen in the short term
Adverse effects (3)
- most common adverse effects are nausea and vomiting, drowsiness, hypotension and abdominal pain
- tachycardia can occur and this is more common in critical care patients.
- less common adverse effects include:
- diarrhoea
- confusion and hallucinations (particularly in the elderly)
- tremor
- paraesthesia
- dizziness
- headache
- syncope
- seizures
- palpitations
- anticholinergic effects such as dry mouth, constipation, blurred vision and urinary retention can also occur
- overdose
- is characterised by neurological symptoms (seizures, hallucination and agitation) and cardiovascular symptoms (coma and tachycardia)
- serotonin toxicity can also occur in overdose, particularly if taken with other serotonergic drugs such as selective serotonin reuptake inhibitors (SSRIs)
Interactions (3)
- use with caution with tricyclic antidepressants due to additive risk of anticholinergic effects
- combination with monoamine oxidase inhibitors (MAOIs) (for example phenelzine, isocarboxazid and tranylcypromine) is contra-indicated due to increased risk of severe hypertension
Consult the summary of product characteristics before prescribing nefopam.
Reference:
- Heel RC, Brogden RN, Pakes GE, Speight TM, Avery GS. Nefopam: a review of its pharmacological properties and therapeutic efficacy. Drugs. 1980;19(4):249-67.
- Kim KH, Abdi S.Rediscovery of nefopam for the treatment of neuropathic pain.Korean J Pain. 2014 Apr;27(2):103-11.
- NHS Specialist Pharmacy Service (January 2024). Use of nefopam for chronic pain