MDSteps Library Preview
You’ve viewed 0 of 5 free topics. Full QBank + CCS + Library is $27/month.
Continue for $27/mo
MDSteps- USMLE® Reference Library

Toxic Alcohol Ingestion — Fomepizole, Adjuncts, and Dialysis Triggers

System: Toxicology • Reviewed: Sep 1, 2025 • Step 1Step 2Step 3

Synopsis:

Methanol/ethylene glycol ingestions cause high anion gap metabolic acidosis and osmolal gap. Start fomepizole immediately, give cofactors (folinic acid/pyridoxine/thiamine), correct acidosis, and consult poison control; initiate hemodialysis for severe toxicity.

Key Points

  • Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
  • Set objective targets (hemodynamic, neurologic, respiratory) and reassess frequently.
  • Plan definitive source control or reperfusion when indicated; document follow‑up and patient education.

Algorithm

  1. Suspect based on HAG metabolic acidosis with osmolal gap and history; call poison control/toxicology.
  2. Start fomepizole immediately; obtain baseline labs and send levels (do not wait).
  3. Correct severe acidosis with bicarbonate; give cofactors depending on suspected alcohol.
  4. Initiate hemodialysis for severe acidosis, visual symptoms (methanol), renal failure, or high levels per criteria.
  5. Continue fomepizole during dialysis with shortened interval; monitor until gap closes and levels undetectable.

Clinical Synopsis & Reasoning

Methanol/ethylene glycol ingestions cause high anion gap metabolic acidosis and osmolal gap. Start fomepizole immediately, give cofactors (folinic acid/pyridoxine/thiamine), correct acidosis, and consult poison control; initiate hemodialysis for severe toxicity.


Treatment Strategy & Disposition

Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced or procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.


Epidemiology / Risk Factors

  • Risk varies by comorbidity and precipitants; see citations for condition‑specific data.

Investigations

TestRole / RationaleTypical FindingsNotes
Serum osmolality and osmolal gapScreeningElevated gapInterpret with ethanol presence
Anion gap, lactate, ABGSeverityHigh anion gap acidosisTrend with therapy
Toxic alcohol levels (send-out)ConfirmationElevated methanol/EGDo not delay therapy

Pharmacology

Medication/InterventionMechanismOnsetRole in TherapyLimitations
Fomepizole 15 mg/kg IV load → 10 mg/kg q12hADH inhibitorImmediateBlocks toxic metabolite formationShorten interval during dialysis
Sodium bicarbonate infusionBufferMinutesTreat severe acidosisMonitor pH/Na+
Folinic acid 1 mg/kg IV q6h (methanol)CofactorHoursEnhance formate metabolism
Pyridoxine 50 mg IV/PO q6h + Thiamine 100 mg IV/PO q6h (EG)CofactorsHoursShift to non-toxic metabolites
HemodialysisRemovalImmediateIndications: severe acidosis, end-organ injury, high levelCoordinate with toxicology

Prognosis / Complications

  • Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.

Patient Education / Counseling

  • Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.

References

  1. EXTRIP Workgroup Recommendations: Toxic Alcohols (2019 update) — Link
MDSteps USMLE Prep

Use the Library, QBank, CCS, and analytics in one study workflow.

You just reviewed Toxic Alcohol Ingestion — Fomepizole, Adjuncts, and Dialysis Triggers. MDSteps helps you turn that review into exam-style practice, missed-item flashcards, and a readiness dashboard that shows what to study next.

  • 16,000+ USMLE-style questions across Step 1, Step 2, and Step 3
  • CCS simulator with timed orders, live vitals, and case feedback
  • Depth-on-Demand™ explanations and Anki-exportable flashcards
  • Library + QBank + analytics for $27/month or $299 lifetime

You’ve reached your MDSteps Library preview limit

Continue with full MDSteps access: Library, adaptive QBank, CCS simulator, and readiness analytics for $27/month or $299 lifetime.

  • Full access to all reference topics
  • 16,000+ USMLE-style questions with teaching-grade rationales
  • Realistic CCS cases with live vitals
  • Exam readiness dashboard & study insights