Drug Dosage Calculator

Estimate a weight-based single dose for selected medicines. Always follow medical guidance and product labeling.

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Select a medicine and enter body weight to estimate a single dose in mg.

Auto-filled based on selected drug.
Safety warning
Do not use this as a substitute for professional advice.
Many medicines have maximum single doses, daily limits, and age-specific rules.
If symptoms are severe or you are unsure, contact a clinician.
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Disclaimer: This tool is for informational purposes only and should not be considered medical advice. Please consult a qualified healthcare professional for diagnosis or treatment.This tool is for informational purposes only and should not be considered medical advice. Please consult a qualified healthcare professional for diagnosis or treatment.

Understanding weight-based dosing

Some medicines are commonly prescribed using weight-based dosing, expressed as milligrams per kilogram (mg/kg). This approach can help tailor a dose to body size, especially in pediatric settings. The basic calculation is straightforward: dose (mg) = weight (kg) × dose per kg (mg/kg). However, safe prescribing is more complex than a single equation.

Many drugs have important constraints, such as maximum single doses, maximum total daily doses, minimum ages, and medical contraindications. Factors like kidney or liver function, other medications, and the reason the medicine is being used can change what is appropriate.

Always verify dosing and frequency with a qualified healthcare professional or the official product labeling.

Disclaimer: This tool is for informational purposes only and should not be considered medical advice. Please consult a qualified healthcare professional for diagnosis or treatment.This tool is for informational purposes only and should not be considered medical advice. Please consult a qualified healthcare professional for diagnosis or treatment.