How is Clark's Rule applied?

Paediatric dose = (weight in lbs / 150) × adult dose. For a 30 lb (13.6 kg) child and adult dose of 500 mg: dose = (30/150) × 500 = 100 mg. This rule is a simplistic historical approximation now largely replaced by weight-based mg/kg dosing.

Is Clark's Rule still used in modern paediatric practice?

Clark's Rule has largely been replaced by weight-based (mg/kg) and body surface area dosing. However, it remains useful for rapid estimation when precise paediatric dosing data are unavailable, such as in disaster scenarios.

Clark's Rule — Paediatric Dose by Body Weight

Calculate paediatric drug dose using Clark's Rule (paediatric dose = weight(lb) / 150 × adult dose) as a historical weight-based dosing method for estimating approximate doses in children.

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Clark's Rule — Paediatric Dose by Body Weight

Frequently Asked Questions

How is Clark's Rule applied?

Is Clark's Rule still used in modern paediatric practice?