Liver failure resulting from deliberate or accidental paracetamol overdose continues to be an important reason for referral to liver transplant centres. Severe hepatic dysfunction often appears 72–96 h after overdose. Liver injury can be prevented by timely administration of the specific antidote, N-acetylcysteine. Unfortunately, administration of N-acetylcysteine is frequently delayed due to late presentation or late administration. While N-acetylcysteine works best if given within 8 h of overdose, it is beneficial at any time period and should always be given if there is concern about significant overdose, irrespective of interval from time of ingestion. Early discussion with liver transplant unit is suggested if there is any doubt or evidence of liver failure.