💊 Acetaminophen (Paracetamol) Dose & Toxicity Threshold
Check acetaminophen (paracetamol) daily and single-dose limits, and assess whether an acute ingestion reaches the toxic threshold or warrants N-acetylcysteine. Instant, browser-side.
Acetaminophen (Paracetamol) Dose & Toxicity Threshold
Weight (kg)
Acute ingested amount (optional) (mg)
When to use
Verify therapeutic dosing and triage an acute overdose by mg/kg ingested. Use the Rumack-Matthew nomogram on a timed 4-hour level for the definitive NAC decision.
How it works
Adult (≥ 50 kg): single ≤ 1 g, daily ≤ 4 g. Child (< 50 kg): ≤ 15 mg/kg/dose, ≤ 75 mg/kg/day. Acute toxic threshold ≥ 150 mg/kg.
Key points
- Lower the ceiling with chronic alcohol use, liver disease, malnutrition/fasting or isoniazid.
- Single acute ingestion ≥ 150 mg/kg (adult ≈ 7.5–10 g) risks hepatotoxicity.
- NAC within 8 hours is nearly fully hepatoprotective.
- Watch for hidden acetaminophen in combination products and for extended-release kinetics.
References
Decision support for licensed clinicians only; not a substitute for clinical judgement, diagnosis or local protocols.