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Toxicology Antidote Dosing Calculator

Antidote dosing for common poisonings: acetaminophen/NAC, opioid/naloxone, benzodiazepine/flumazenil, organophosphate/atropine, digoxin/DigiFab.

Inputs

Results

Loading Dose (mg)

10,500

Maintenance / Repeat Dose (mg)3,500
Treatment Duration (hours)21
Maximum Total Dose (mg)21,000
Route (1=IV, 2=PO, 3=IM, 4=IV+IM)1
Antidote Selected (1-5)1
How to Use This Calculator
  1. Enter Patient Weight (kg).
  2. Select the Toxin Type from the dropdown (organophosphate, opioid, acetaminophen, TCA, benzodiazepine, etc.).
  3. Review Loading Dose (mg), Maintenance/Repeat Dose (mg), and Treatment Duration (hours).
  4. Check Maximum Total Dose (mg) to avoid antidote toxicity.
  5. Note Route of Administration (IV, PO, IM, or IV+IM) for the selected antidote.

How the result changes with Patient Weight (kg)

Patient Weight (kg)Loading Dose (mg)
314,650
10615,900
19529,250
27040,500

What each input means

Patient Weight (kg)
Patient weight in kilograms.
Toxin Type
1 = Acetaminophen (NAC), 2 = Opioid (Naloxone), 3 = Benzodiazepine (Flumazenil), 4 = Organophosphate (Atropine), 5 = Digoxin (DigiFab).

What each result means

Loading Dose (mg)
Initial antidote dose. For DigiFab, this is in mg (÷40 for vials).
Maintenance / Repeat Dose (mg)
Subsequent dose or second infusion rate. Context depends on antidote.
Treatment Duration (hours)
Expected duration of antidote therapy or observation period.
Maximum Total Dose (mg)
Maximum recommended total dose. 0 = no fixed maximum (titrate to effect).
Route (1=IV, 2=PO, 3=IM, 4=IV+IM)
Recommended administration route.
Antidote Selected (1-5)
Echo of selected toxin/antidote pair.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    Patient Weight (kg) = 70, Toxin Type = 1 = 2 input(s) provided
  2. Calculate Loading Dose
    Loading Dose
    10500 = 10500
  3. Calculate Maintenance / Repeat Dose
    Maintenance / Repeat Dose
    3500 = 3500
  4. Calculate Treatment Duration
    Treatment Duration
    21 = 21

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