TOX-DOSE-CAP-ERR-002 medical data_error ai_generated true

AI calculates fomepizole loading dose for methanol poisoning using patient's actual body weight exceeding 100 kg without capping at 100 kg, causing tenfold overdose

ID: medical/ethylene-glycol-methanol-dosing

Also available as: JSON · Markdown · 中文
80%Fix Rate
85%Confidence
1Evidence
2024-05-20First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
Antizol Prescribing Information 2023 active — — —
Goldfrank's Toxicologic Emergencies 11th Ed active — — —
EXTRIP Workgroup Guidelines for Methanol Poisoning 2022 active — — —

Root Cause

Fomepizole (Antizol) loading dose is 15 mg/kg IV, but the recommended maximum single dose is 1.5 g (for patients >100 kg, use ideal body weight or cap at 100 kg) to avoid toxicity from the propylene glycol vehicle; AI ignored this cap for a 150 kg patient, calculating 2.25 g.

generic

中文

甲吡唑（Antizol）负荷剂量为15 mg/kg静脉注射，但推荐单次最大剂量为1.5 g（体重>100kg的患者使用理想体重或上限100kg），以避免丙二醇溶剂的毒性；AI对150kg患者未设上限，计算为2.25g。

Official Documentation

https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=8f7a6b1a-0c5d-4b3e-9f2a-1e8c7d6b5a4c

Workarounds

  1. 95% success Cap the weight at 100 kg for dose calculation: `dose_mg = min(patient_weight_kg, 100) * 15`. For a 150 kg patient: 100 * 15 = 1500 mg = 1.5 g (one vial). Verify with pharmacy: `python -c "print(min(150,100)*15)"` 
    Cap the weight at 100 kg for dose calculation: `dose_mg = min(patient_weight_kg, 100) * 15`. For a 150 kg patient: 100 * 15 = 1500 mg = 1.5 g (one vial). Verify with pharmacy: `python -c "print(min(150,100)*15)"`
  2. 90% success Use ideal body weight (IBW) for obese patients: IBW (males) = 50 + 0.91*(height_cm - 152.4), IBW (females) = 45.5 + 0.91*(height_cm - 152.4). Then calculate dose = IBW * 15 mg/kg. Document in MAR: `Fomepizole 1.5 g IV (capped at 100 kg IBW)` 
    Use ideal body weight (IBW) for obese patients: IBW (males) = 50 + 0.91*(height_cm - 152.4), IBW (females) = 45.5 + 0.91*(height_cm - 152.4). Then calculate dose = IBW * 15 mg/kg. Document in MAR: `Fomepizole 1.5 g IV (capped at 100 kg IBW)`

中文步骤

  1. Cap the weight at 100 kg for dose calculation: `dose_mg = min(patient_weight_kg, 100) * 15`. For a 150 kg patient: 100 * 15 = 1500 mg = 1.5 g (one vial). Verify with pharmacy: `python -c "print(min(150,100)*15)"`
  2. Use ideal body weight (IBW) for obese patients: IBW (males) = 50 + 0.91*(height_cm - 152.4), IBW (females) = 45.5 + 0.91*(height_cm - 152.4). Then calculate dose = IBW * 15 mg/kg. Document in MAR: `Fomepizole 1.5 g IV (capped at 100 kg IBW)`

Dead Ends

Common approaches that don't work:

  1. 65% fail

    Using lean body weight formula (Boer) for all patients — underestimates dose for obese patients and may lead to subtherapeutic levels

  2. 55% fail

    Assuming the dose can be rounded up to nearest vial (1.5 g vial) — 2.25 g requires opening two vials and discarding part, risking contamination

  3. 75% fail

    Using adjusted body weight (IBW + 0.4*(ABW-IBW)) — not validated for fomepizole and may still exceed safe limits