Acetaminophen NAC IV Dosing

N-acetylcysteine dosing for acetaminophen poisoning: computes the per-bag milligrams for the three-bag (21 h) or two-bag (SNAP) IV regimen, capping dosing weight at 110 kg.

Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.

Example

Body weight
120
IV NAC regimen
Three-bag (21-hour) -- 150, 50, 100 mg/kg

Result: NAC three-bag (21 h), dosing weight capped at 110 kg (entered 120 kg): bag 1 16500 mg over 1 h, bag 2 5500 mg over 4 h, bag 3 11000 mg over 16 h (total 33000 mg).

The tool opens with these values already filled in. Replace them with your own.

What the result means

Three-bag (21 h)
150 mg/kg over 1 h, then 50 mg/kg over 4 h, then 100 mg/kg over 16 h (300 mg/kg total).
Two-bag (SNAP)
200 mg/kg over 4 h, then 100 mg/kg over 16 h. Dosing weight capped at 110 kg. Confirm against your institutional protocol and a second check.

What you enter

  • Body weight (kg)
  • IV NAC regimen
How this is calculated

Prescott LF, Illingworth RN, Critchley JA, Stewart MJ, Adam RD, Proudfoot AT. Intravenous N-acetylcysteine: the treatment of choice for acetaminophen poisoning. BMJ. 1979;2(6198):1097-1100; two-bag SNAP per Bateman DN, et al. Lancet. 2014;383:697-704. Read the source ↗

A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.

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Built by Clay Good. Source on GitHub.