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Calculate weight-based medication doses and liquid volumes using mg/kg formulas.
Medication dosage calculation uses weight-based formulas (mg/kg) to determine the correct amount of a drug to administer, accounting for body weight and medication concentration.
⚠️ Educational use only. Always follow your healthcare provider's dosing instructions. This calculator does not replace professional medical advice.
| Drug | Dose | Frequency |
|---|---|---|
| Acetaminophen (child) | 10-15 mg/kg | Every 4-6 hours |
| Ibuprofen (child) | 5-10 mg/kg | Every 6-8 hours |
| Amoxicillin | 25-50 mg/kg | Every 8-12 hours |
| Acetaminophen (adult) | 500-1000 mg | Every 4-6 hours |
| Ibuprofen (adult) | 200-400 mg | Every 4-6 hours |
Formula
Total Dose (mg) = Weight (kg) × Dose (mg/kg) | Volume (mL) = Total Dose ÷ Concentration (mg/mL)Weight = Patient body weight in kilograms
Dose (mg/kg) = Prescribed milligrams per kilogram of body weight
Concentration = Medication strength (mg per mL for liquids)
Worked Example
25 kg child, 10 mg/kg dose, liquid 100 mg/5 mL
Did you know? Medication errors are the third leading cause of death in the US, with dosing errors being the most common type. Weight-based dosing calculations, when performed correctly, reduce pediatric medication errors by up to 68% (source: Journal of Patient Safety).
Sources
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