PSI Pharmaceutical Calculations

Question 1

A patient requires amoxicillin 250 mg. The available suspension contains 125 mg/5 mL. What volume should be dispensed per dose?

Accepted Answer

10 mL

Answer

250 mg ÷ (125 mg/5 mL) = 10 mL per dose.

Question 2

A prescription states 'paracetamol 0.5 g'. Tablets available are 500 mg. How many tablets should be dispensed per dose?

Accepted Answer

1 tablet

Answer

0.5 g equals 500 mg, which is exactly one 500 mg tablet.

Question 3

A 2% w/v solution contains how many grams of solute in 250 mL?

Accepted Answer

5 g

Answer

2% w/v = 2 g per 100 mL; therefore 250 mL contains 2 × 2.5 = 5 g.

Question 4

A morphine injection contains 10 mg/mL. A patient requires a 15 mg dose. What volume should be drawn up?

Accepted Answer

1.5 mL

Answer

15 mg ÷ 10 mg/mL = 1.5 mL.

Question 5

Digoxin tablets are available as 62.5 micrograms. A patient requires 125 micrograms per dose. How many tablets should be given?

Accepted Answer

2 tablets

Answer

125 micrograms ÷ 62.5 micrograms = 2 tablets per dose.

PSI Pharmacy Practice Test