WEDINOS DAN 24/7 Public Health Wales Welsh Government Naloxone saves lives


Type Psychoactive
Legal Status Class B
Codeine is a opioid analgesic first isolated from opium in 1832. Codeine toxicity is due to opioid effects. The fatal dose is likely to be variable between individuals depending on tolerance and rates of metabolic conversion to morphine. As codeine is metabolised to morphine, the effects may be prolonged after overdose. This is especially the case in patients with renal impairment and the elderly.
The acutely lethal dose of codeine for an adult has been estimated at 0.5 – 1.0g. Severe opiate toxicity produces depression of the respiratory and central nervous systems and pin-point pupils. If untreated the depression of the level of consciousness can lead to deep coma, convulsions and respiratory arrest. The effects in overdosage will be potentiated by simultaneous ingestion of alcohol and other centrally acting drugs.
Short Term Effects
Nausea, vomiting, nightmares, anxiety, agitation, euphoria, dysphoria, depression, paranoia and hallucinations. Opioids, in particular codeine, can cause histamine release, most commonly causing urticaria and pruritis.