ICU Decoded › Library › Ward Pathways › Emergency / Toxicology › Paracetamol Overdose
Paracetamol OverdoseUrgent
Emergency / Toxicology · Ward Pathways · Locked — free with a referral
By Dr Javed Akhtar · Last reviewed 2 October 2026
Presentation Took 40 tablets of paracetamol 500 mg (20 g) 5 h ago; 60 kg; nausea only; 4-hour level pending
Red flags Encephalopathy INR rising pH <7.30 Hypoglycaemia Oliguria
Differential diagnosis Other hepatotoxins (mushrooms, herbal, alcohol) Viral hepatitis Ischaemic hepatitis Co-ingestants
When to admit, call ICU or discharge Admit: Level above the line, staggered/late/unknown time, abnormal LFT/INR, or any high-risk ingestionICU: Acute liver failure, encephalopathy, acidosisTransplant: King's College criteria met
Key points NAC is almost 100% protective if started within 8 h. The four-hour level is meaningless before 4 h. Paracetamol is the commonest drug overdose worldwide — combination cold/pain products hide extra paracetamol.
Never Wait for a level before NAC in late, staggered or unknown-time ingestions Use the nomogram for staggered ingestions Stop NAC early because the patient looks well Give vitamin K or FFP routinely (INR is a prognostic marker)
Common mistakes Waiting for levels Stopping NAC too early Nomogram misuse Missing massive ingestion dosing
Disposition and follow-up Ward on NAC; liver unit if criteria met; psychiatry before discharge.
Locked ABCDE first moves The step-by-step decision sequence Order set Monitoring timeline and escalation triggers Treatment doses and preparation Discharge package Open the full pathway in Ward Pathways
Free with a referral from any ICU Decoded member, or by applying with your medical registration. How access works .
← Tricyclic Antidepressant Overdose · Aspirin / Salicylate Overdose →
More Emergency / Toxicology pathways
Part of Emergency / Toxicology in Ward Pathways — open the interactive version .