Dosage Calculator - Weight, BSA, Age-Based Drug Dosing

Calculate drug dosages by weight, BSA, and age with common drug database and max dose warnings. Medical reference tool.

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Patient Weight (kg)Age (years)Body Surface Area (m²)Drug

Result

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calculated dose

How it works

Dosage Calculator - Weight, BSA, Age-Based Drug Dosing

Calculate drug dosages based on weight (mg/kg), BSA (mg/m²), or age with a database of common medications.

Provides dose ranges, maximum limits, unit conversions, and printable schedules for pediatric and adult patients.

Read full guide & technical breakdown

Never use these calculations for actual dosing. Always consult official prescribing information and a qualified healthcare professional.

FAQ

Common Questions

How do I calculate weight-based dosing?

Weight-based dosing multiplies the patient weight (kg) by the prescribed dose per kg. For example: 15 mg/kg for a 20 kg child = 300 mg. Always verify with official dosing guidelines.

What is BSA-based dosing?

Body Surface Area (BSA) dosing uses the patient's BSA (m²) multiplied by the dose per m². BSA is calculated using height and weight. This method is commonly used for chemotherapy and some pediatric medications.

When should I use age-based dosing?

Age-based dosing is used when weight-based dosing is not available. It provides approximate dose ranges for different age groups. Weight-based dosing is generally more accurate when weight is available.

What are maximum dose limits?

Maximum dose limits prevent overdose. Even if a weight-based calculation yields a higher dose, never exceed the maximum recommended single dose or daily dose for the patient's age group.

Can I use this for emergency dosing?

This calculator is for educational reference only. In emergencies, use verified drug references, clinical protocols, and consult with medical professionals. Always double-check critical dose calculations.

How do I convert between units?

Common conversions: 1 kg = 2.2 lbs, 1 tsp = 5 mL, 1 tbsp = 15 mL, 1 oz = 30 mL. Our calculator handles unit conversions automatically when you select the appropriate units.

Dosage Calculator - Weight, BSA, Age-Based Drug Dosing

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Dosage Calculator - Weight, BSA, Age-Based Drug Dosing

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