Example :
Calculate the dose of Amoxicillin suspension in mLs for a patient weighing 20 pounds. The dose required is 50 mg/kg/day divided three times daily and the suspension comes in a concentration of 250 mg / 5 ml
Step 1 : If the patient weight is in pounds convert it to kilograms
22 pounds × 0.45359237 = 9.979 kilograms
Step 2 : Calculate the daily dose in milligrams
50 × 9.979 = 498.951 mg per day
Step 3 : Check if the calculated daily dose exceeds the maximum daily dose
498.951 mg per day does not exceed the maximum daily dose
Step 4 : Divide the daily dose by the frequency
498.951 ÷ 3 = 166.317 mg per dose repeated three times daily
Step 5 : Convert the milligrams dose to milliliters volume
166.317 × 5 ÷ 250 = 3.3263 ml per dose repeated three times daily
Step 6 : Rounding the volume
The final answer is
Amoxicillin 250 mg / 5 ml Suspension
Give 3.3 ml three times daily