Coproxamol

This is dextropropoxythene and paracetamol (in a combination of 32.5 mg of dextroproxyphene with 325mg of paracetamol).

• dextropropoxyphene is well absorbed and metabolised in the liver. It has a half-life of 12 hours
• dextropropoxyphene does not commonly causes adverse effects in short courses of therapeutic doses. Note though that chronic usage may cause constipation and overdose may cause similar effects to morphine
• there is no evidence that dextropopoxythene 62.5 mg or 100 mg in combination with paracetamol 650 mg, given as a single dose, is more effective than paracetamol 650 mg given alone in the relief of ACUTE pain e.g. after episiotomy, tooth extraction, orthopaedic surgery (2)
• there is no robust evidence that co-proxamol is any more effective than full strength paracetamol in the management of chronic pain (3)
• problems of coproxamol in overdose (2)
  • in 2004 it was reported that, in England and Wales, between 300 and 400 people die each year following deliberate or accidental overdose with co-proxamol (Distalgesic; Cosalgesic; Dolgesic), a fixed-dose combination of paracetamol (325mg) and dextropropoxyphene (32.5mg) indicated for the treatment of mild to moderate pain
  • combination with alcohol or CNS depressants particularly hazardous and may cause fatal apnoea or cardiac arrhythmia

Check the summary of product characteristics before prescribing this drug.

Reference:

1. Drug and Therapeutics Bulletin (1998); 36 (10): 80
2. Current Problems in Pharmacovigilance (2004); 30:1-12.
3. MeReC Bulletin (2006);16 (4):13-16.