Adoctor orders 400 mg of an antibiotic for a 2year child who weighs 30.8 pounds. the medication is to be taken every 12 hours. the label on the medication shows that between 50 and 75 mg/kg. per day is the appropriate dosage range. determine if the dosage ordered by the doctor id within the appropriate range.

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You have to do a cross product in order to transform your pounds in kg :

1 pound = 0,454 kg
30,8 pounds = × kg

(0,454 • 30,8) ÷ 1 → 0,454 • 30,8 = 13,98 kg

The child weighs 13,98 kg

⓶
You have to calculate the minimum dose (which is 50) and the maximum dose (which is 75) per day according to the children’s weight. You have to do cross products again :

50 mg → 1 kg
× mg → 13,98 kg

(50 • 13,98) ÷ 1 → 50 • 13,98 = 699 mg per day

75 mg → 1 kg
× mg → 13,98 kg

(75 • 13,98) ÷ 1 → 75 • 13,98 = 1048,5 mg per day

The appropriate range would be from 699mg to 1048,5mg per day.

⓷
The dosage ordered by the doctor is 400mg for each 12 hours. There is two times 12 hours in a day (12 • 2 = 24hours), which means that you need to multiply the dosage ordered by two in order to know the daily dosage ordered :

400 • 2 = 800 mg per day

Answer : 800mg per day is within the appropriate range for a child this weight!

I hope this helped! ☻