How is the Rumack-Matthew nomogram used?

Plot serum acetaminophen level at known time post-single acute ingestion; levels above the treatment line (150 μg/mL at 4h, decreasing with time) require NAC treatment; only applies to single acute ingestion with known time.

What is the IV NAC protocol?

21-hour protocol: 150 mg/kg IV over 1h (loading), then 50 mg/kg over 4h, then 100 mg/kg over 16h (total 300 mg/kg over 21h); 20-hour SNAP protocol available as alternative with lower anaphylactoid rates.

When should NAC be given regardless of nomogram?

NAC immediately if: staggered or unknown ingestion, unknown timing, hepatotoxic symptoms (jaundice, RUQ pain, elevated LFTs), or time post-ingestion >8-12 hours (nomogram less reliable).

What is the poor prognostic indicator in acetaminophen hepatotoxicity?

King’s College Criteria: pH 6.5 + creatinine >3.4 mg/dL + grade III-IV encephalopathy; MELD >25 also predictive; indicates need for urgent liver transplant evaluation.

Can NAC be given orally instead of IV?

Oral NAC 140 mg/kg loading + 70 mg/kg every 4h × 17 doses (72h total) is an effective alternative; IV preferred for vomiting, altered mental status, or severe hepatotoxicity; oral has higher vomiting rate.

Acetaminophen Toxicity Rumack-Matthew Nomogram

Applies the Rumack-Matthew nomogram to determine N-acetylcysteine (NAC) treatment necessity based on serum acetaminophen level and hours post-ingestion, with NAC dosing protocol for IV and oral routes.

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Frequently Asked Questions

How is the Rumack-Matthew nomogram used?

What is the IV NAC protocol?

When should NAC be given regardless of nomogram?

What is the poor prognostic indicator in acetaminophen hepatotoxicity?

Can NAC be given orally instead of IV?