Enter patient and regimen details
Use label-based defaults or clinician-entered arithmetic. Results appear above this form after calculation.
Example data table
These examples are arithmetic demonstrations for the interface. They still require independent verification before use.
| Scenario | Weight | Basis | Doses/day | Daily total | Per dose |
|---|---|---|---|---|---|
| Pediatric oral serious example | 18 kg | 12 mg/kg/day | 4 | 216 mg/day | 54 mg/dose |
| Pediatric IV severe example | 25 kg | 40 mg/kg/day | 4 | 1000 mg/day | 250 mg/dose |
| Adult oral severe example | Fixed adult | 450 mg every 6 hours | 4 | 1800 mg/day | 450 mg/dose |
| Preterm PMA ≤ 32 weeks example | 2.8 kg | 5 mg/kg every 8 hours | 3 | 42 mg/day | 14 mg/dose |
Formula used
Daily dose (mg/day) = weight (kg) × selected mg/kg/day
Daily dose (mg/day) = BSA (m²) × selected mg/m²/day
Per dose (mg) = daily dose ÷ doses per day
Rounded per dose (mg) = nearest chosen rounding step
Oral volume (mL) = rounded per dose ÷ oral concentration
Injection stock volume (mL) = rounded per dose ÷ stock concentration
Final infusion volume (mL) = rounded per dose ÷ final infusion concentration
Minimum infusion time (min) = rounded per dose ÷ 30 mg/min
For fixed adult oral regimens, the calculator uses the chosen mg per dose and multiplies by the number of daily doses.
How to use this calculator
- Choose the age group and route.
- Pick label-based defaults or a custom arithmetic mode.
- Enter weight, and BSA only when needed.
- Set doses per day, concentrations, rounding, and duration.
- Press calculate to display the result above the form.
- Review per-dose, daily, volume, and infusion timing outputs.
- Check every warning, then confirm against official references.
- Use the CSV or PDF buttons to save the summary.
FAQs
1) Is this calculator safe for direct prescribing?
No. It is an educational arithmetic tool. Every result needs confirmation with current prescribing information, indication-specific guidance, patient factors, and local antimicrobial policies.
2) Does it replace infectious disease or pharmacy review?
No. The page speeds up math only. Final dosing decisions still require clinical judgment, allergy review, organ function assessment, and confirmation of organism coverage.
3) Why do some routes force different defaults?
Because the official labeling uses different adult, pediatric, neonatal, and preterm dose structures for oral and parenteral products. The form mirrors those structures.
4) What does the rounding step do?
It rounds the exact per-dose calculation to a practical administration amount. Rounding should still be checked against formulation strengths and clinical acceptability.
5) Why is there both stock and infusion concentration?
Stock concentration estimates the amount drawn up from the vial. Final infusion concentration estimates the diluted IV bag volume and helps flag concentration limits.
6) Can I use BSA instead of weight?
The BSA option is included for pediatric parenteral label arithmetic. If your protocol uses another basis, choose a custom mode and verify independently.
7) Does the calculator adjust for renal or hepatic impairment?
No automatic adjustment is made. The result card only adds reminder notes. Patient-specific organ dysfunction still requires direct review of current guidance and monitoring plans.
8) What should I export: CSV or PDF?
Use CSV for spreadsheet review or audit trails. Use PDF when you want a print-friendly summary to discuss, sign off, or archive.