Safe Dose Range Calculator
Check whether an ordered dose falls within a drug’s safe mg/kg range for the patient’s weight, with the low and high daily limits shown.
How it works
Safe low = weight × low mg/kg/day · Safe high = weight × high mg/kg/day · Compare against the ordered daily total
Before giving a weight-based medicine, nurses check that the ordered amount sits inside the drug’s recommended safe dose range for that patient’s weight. Multiply the low and high mg/kg/day figures by the weight to get the daily window, then compare the ordered total against it: below range risks being ineffective, above range risks toxicity and must be questioned. Enter the exact range from the drug reference — ranges differ by indication, age and route.
Worked example
A 25 kg child with a reference range of 20–40 mg/kg/day has a safe window of 25 × 20 = 500 mg to 25 × 40 = 1,000 mg per day. An order for 750 mg/day is inside that range (equivalent to 30 mg/kg/day), so it passes the check.
Frequently asked questions
What do I do if the order is above range?
Do not administer it. Hold the dose, recheck your figures and the reference range, and contact the prescriber or pharmacist to clarify or correct the order. An above-range result is a stop-and-verify signal, not a rounding issue.
Where do the mg/kg limits come from?
From the drug’s labeling or an authoritative reference, and they depend on the indication, patient age and route. Enter the specific low and high values for the exact situation; a range for one infection or age group does not transfer to another.
Should I compare per dose or per day?
Match the reference. This tool compares daily totals, so enter a daily range and the total daily ordered amount. If your reference is per dose, multiply the per-dose limits by the number of doses first, or compare a single dose against per-dose limits instead.
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Educational estimate only — not medical advice, and no substitute for a clinician, pharmacist or the product label. Every dose, rate and volume must be independently verified against the actual drug, order and patient before administration. Do not use this tool to self-treat or to bypass an institution’s double-check policy.