A daily amount must be divided by doses per day; a per-dose amount is given at each stated interval.
- Arithmetic example: 25 mg/kg/day × 20 kg = 500 mg/day.
- Every 12 hours means two doses: 250 mg each.
- At 250 mg/5 mL, each dose is 5 mL.
- Check indication, age, concentration, and maxima separately; this is arithmetic, not a patient prescription.