Acetaminophen (Rumack-Matthew) nomogram

Rumack-Matthew nomogram (US treatment line 150 ug/mL at 4 h): treatment-line level at the entered time post single acute ingestion and whether the measured level is above it.

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

Example

Hours since single acute ingestion
4 h
Serum acetaminophen
160 ug/mL

Result: Treatment line 150 ug/mL at 4 h; 160 ug/mL is above the line -> NAC indicated. Refuses outside 4-24 h.

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

What you enter

  • Hours since single acute ingestion (4-24 h)
  • Serum acetaminophen
How this is calculated

Rumack BH, Matthew H. Pediatrics. 1975;55(6):871-876; U.S. treatment line 150 ug/mL at 4 h (Rumack-Matthew). Valid only for a single acute ingestion with a known time, level drawn >=4 h. 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.