Question

Calculate the following dosages according to kilogram of body weight:

a. The physician ordered Zovirax capsules 5 mg/kg every 8 hours for 7 days for a patient who has a diagnosis of herpes zoster. The patient weighs 132 pounds. Convert pounds to kilograms and then calculate the prescribed dosage.

b. The physician ordered aminophylline 7.5 mg/kg for a child who weighs 66 pounds. Convert pounds to kilograms and then calculate the prescribed dosage.

c. The physician ordered Rocephin 50 mg/kg in two divided doses for a child who weighs 44 pounds. Convert pounds to kilograms and then calculate the prescribed dosage.

d. The physician ordered chloral hydrate 25 mg/kg for a child who weighs 55 pounds. Convert pounds to kilograms and then calculate the prescribed dosage. e. The physician ordered a medication of 50 mg/kg/day in divided doses at 8-hour intervals. The patient weighs 110 pounds. Convert pounds to kilograms and then calculate the prescribed dosage.

Answer 1

a) 300 mg every 8 hours for 7 days

Given that,

The weight of the patient is 132 pounds.

1 pound = 0.453592 Kg

So, 132 pound = 59.8742kg

Which on rounding off, we get 59.9 kg which is approximately equal to 60kg

Given: zovirax capsules 5mg/ kg every 8 hours for 7 days.

Therefore, the prescribed dose is

60 × 5 = 300 mg

Hence the prescribed dose is equal to 300 mg every 8hours for 7 days.

b) 225 mg of aminophylline

  Given that, aminophylline 7.5mg/kg

The weight of the patient is 66 pounds

1 pound = 0.453592kg

So, 66 pound = 29.9371kg

On rounding off, we get 30kg

Therefore, prescribed dose is equal to

30 × 7.5 = 225 mg

Hence, the prescribed dose is equal to 225mg of aminophylline.

c) 500 mg twice daily

Given that : Rocephin 50mg/kg in 2 divided doses.

The weight of the patient is 44 pounds.

1pound = 0.453592kg

So 44 pound = 19.9581kg

Which is approximately equal to 20kg.

Dose per day is 20 × 50 = 1000mg

As per prescription, the drug should be given in 2 divided doses

So, 1000/2 = 500kg

Therefore, the prescribed dose is equal to 500mg twice daily.

d) 625mg

Given: Chloral hydrate 25mg/kg

The weight of the patient is 55 pounds

1 pound = 0.453592kg

So, 55pound = 24.9476kg

Which is approximately equal to 25kg

Therefore, the prescribed dose is

25 × 25 = 625mg

Hence, the prescribed dose is equal to 625mg.

e) 833mg, 3 times a day

Given: medication of 50mg/kg/day in divided doses at 8 hour interval

Patient weight is 110 pounds

1 pound = 0.453592kg

So, 110 pound = 49.8952kg

On rounding off we get 49.9 kg which is approximately equal to 50kg.

To calculate the dose per day, multiply the mg/kg dose with the weight of the patient

i.e, 50 × 50 = 2500mg/day

2500mg/ day should be given at an interval of 8 hours.

8 hour interval means 3 times a day.

To calculate the dose per each adminstaration, divide dose per day with frequency

i.e, 2500/3 = 833.33

On rounding off we get, 833mg

Prescribed dose is 833mg, three times a day.