🚑 EmergencyToxicology / EmergencyStudentInternResident

Paracetamol Poisoning

Also known as: acetaminophen overdose · paracetamol overdose · NAC

Acetaminophen overdose can cause fatal hepatotoxicity, often with few early symptoms. N-acetylcysteine (NAC) is a highly effective antidote when given in time.

Source · Reviewed 2026-08-15 · v1.0— AI-assisted draft — verify against the nomogram / poison centre before clinical use.

⚕️ Education only — not medical advice. Verify against the latest official guideline and your local protocol; confirm every drug dose against the cited source before clinical use.

Who gets it

Deliberate self-harm or accidental overdose; higher risk with malnutrition, chronic alcohol use and enzyme-inducing drugs.

Red flags — escalate / refer

Staggered or large ingestion, late presentation, or signs of liver injury (RUQ pain, jaundice, encephalopathy, coagulopathy) → high risk; involve toxicology/liver unit.

Work-up / diagnosis

1Take a timed paracetamol level from ~4 hours post-ingestion and plot on the treatment nomogram.
2Check LFTs, INR, renal function, glucose and a venous gas.
3Establish the timing, amount and type of ingestion (single vs staggered).

Management — overview

Give activated charcoal if the patient presents within ~1 hour of a significant ingestion.
Start N-acetylcysteine (NAC) per the nomogram/timing — treat empirically if presentation is late, staggered, or the level will be delayed; NAC works best early but still helps late.
Supportive care; monitor INR/LFTs; refer to a liver unit for signs of acute liver failure.

In-depthFull dosing & advanced protocol

Drug dosing

N-acetylcysteine (NAC)

Antidote (per nomogram/timing)

Adult dose: IV regimen by weight and timing, per local protocol
Route: Intravenous

Caution: Do not wait for symptoms; treat staggered/late ingestions empirically. Watch for anaphylactoid reactions.

WHOWHO Model List of Essential Medicines (electronic EML) (2025 (24th)) ↗

Activated charcoal

Recent significant ingestion (<1 h)

Adult dose: Single dose orally
Route: Oral

WHOWHO Model List of Essential Medicines (electronic EML) (2025 (24th)) ↗

Nomogram, high-risk & liver failure

Use the paracetamol treatment nomogram against the timed level; treat empirically when timing is uncertain or ingestion is staggered.
Monitor INR, LFTs and creatinine; a rising INR indicates hepatotoxicity.
Refer for transplant assessment using King's College criteria in severe hepatotoxicity.

ICMRStandard Treatment Workflows (STWs), India — Dept. of Health Research & ICMR (2022+) ↗

References

Guidelines change. If something here is out of date, tell us — we keep these current.

🚩 Report outdated / suggest update

More protocols

AnaphylaxisAcute, life-threatening systemic hypersensitivity with airway, breathing or circulation compromise within minutes of a trigger. Intramuscular adrenaline is the immediate, life-saving treatment.Snakebite EnvenomationA medical emergency from a venomous snakebite. In India the “Big Four” (cobra, krait, Russell's viper, saw-scaled viper) cause neurotoxic and/or haemotoxic envenomation. Polyvalent anti-snake venom (ASV) is the antidote; many bites are “dry”.Sepsis & Septic ShockLife-threatening organ dysfunction from a dysregulated host response to infection. Early recognition and the “hour-1 bundle” save lives; septic shock adds fluid-refractory hypotension.

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👤 Who gets it

🚩 Red flags — escalate / refer

🔎 Work-up / diagnosis

🧭 Management — overview

💊 Drug dosing

N-acetylcysteine (NAC)

Activated charcoal

📈 Nomogram, high-risk & liver failure

📚 References

More protocols

👤 Who gets it

🚩 Red flags — escalate / refer

🔎 Work-up / diagnosis

🧭 Management — overview

💊 Drug dosing

N-acetylcysteine (NAC)

Activated charcoal

📈 Nomogram, high-risk & liver failure

📚 References

More protocols

Who gets it

Red flags — escalate / refer

Work-up / diagnosis

Management — overview

Drug dosing

Nomogram, high-risk & liver failure

References

Who gets it

Red flags — escalate / refer

Work-up / diagnosis

Management — overview

Drug dosing

Nomogram, high-risk & liver failure

References