APC Pharmaceutical Calculations 2

Question 1

An IV infusion of 1000 mL must be administered evenly over 8 hours. What is the required flow rate in mL/hour?

Accepted Answer

125 mL/hr

Answer

Flow rate = 1000 mL ÷ 8 hours = 125 mL/hour.

Question 2

A child weighing 20 kg needs 10 mg/kg of ibuprofen. The available suspension contains 100 mg/5 mL. What volume is required per dose?

Accepted Answer

10 mL

Answer

Required dose: 20 kg × 10 mg/kg = 200 mg; volume: (200 ÷ 100) × 5 = 10 mL.

Question 3

An IV infusion set delivers 20 drops/mL. The prescribed rate is 150 mL/hour. What is the required drip rate in drops per minute?

Accepted Answer

50 drops/min

Answer

Drip rate = (150 mL/hr × 20 drops/mL) ÷ 60 min = 50 drops/min.

Question 4

A dobutamine infusion is prescribed at 2 mcg/kg/min for a 70 kg patient. What is the total infusion rate in mcg/min?

Accepted Answer

140 mcg/min

Answer

Rate = 2 mcg/kg/min × 70 kg = 140 mcg/min.

Question 5

A pharmacist prepares 50 g of a 1% w/w ointment. How many grams of active drug are needed?

Accepted Answer

0.5 g

Answer

1% w/w of 50 g = 0.01 × 50 = 0.5 g of active drug.

(APC) Australian Pharmacy Council Practice Test