Weight-Based Dose Calculator (mg/kg & mg/kg/day)
Calculates single dose (mg) and total daily dose (mg/day) from patient body weight (kg) and prescribed mg/kg regimen.
⚠️ Educational Calculation & Clinical Safety Safeguard: Always verify that the calculated weight-based dose does not exceed the maximum adult single or daily ceiling dose. Educational calculations do not replace clinician assessment, patient-specific laboratory monitoring, or institutional prescribing protocols.
Interactive Calculator
Allowed physiological/compounding range: 0.5 to 300 kg
Allowed physiological/compounding range: 0.001 to 2000 mg/kg/dose
Allowed physiological/compounding range: 1 to 24 doses/day
Calculated Output (mg/dose & mg/day)
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Step-by-Step Mathematical Derivation & Explanation:
Validated Formula & Conversion Rules
Single Dose (mg) = Weight (kg) × Dose (mg/kg/dose); Total Daily Dose (mg/day) = Single Dose (mg) × Doses/dayWorked Clinical Example
A 60 kg adult prescribed Paracetamol 15 mg/kg/dose every 8 hours (3 doses/day): Single Dose = 60 × 15 = 900 mg; Total Daily Dose = 900 × 3 = 2700 mg/day (within 4000 mg/day adult ceiling).
Rounding Rules, Clinical Interpretation, Assumptions & Known Limitations
- 1. Purpose: Calculates single dose (mg) and total daily dose (mg/day) from patient body weight (kg) and prescribed mg/kg regimen.
- 2. Required Inputs & Validated Units: Patient Weight (kg, range 0.5–300), Prescribed Dose per kg (mg/kg/dose, range 0.001–2000), Doses per Day (Frequency) (doses/day, range 1–24)
- 3. Output Unit:
mg/dose & mg/day - 4. Result Interpretation Notes: Compare single and daily mg output against NLEM 2022 / IP 2022 adult ceiling doses before dispensing.
- 5. Rounding Guidance: Round oral tablet doses to nearest practical scored tablet strength; round liquid doses to 0.1 mL.
- 6. Mathematical & Clinical Assumptions: Assumes linear mg/kg pharmacokinetic scaling across the entered weight range.
- 7. Known Limitations & Contraindications to Formula Use: In severe obesity (BMI >= 30 kg/m²), hydrophilic drugs may require Ideal or Adjusted Body Weight (see CALC-F3) rather than total body weight.
- 8. Supporting Compendial & Clinical References: Indian Pharmacopoeia (IP 2022), National Formulary of India (NFI), British National Formulary (BNF), and NCBI Bookshelf Clinical Pharmacology Compendia.