A patient is prescribed 6.25 mg of a drug. The tablets on the ward contain 12.5 mg each. How many tablets n do you give? The tablets are scored, so they can be broken in half.
Dosage calculations worksheet with answers
1.Easy
6.25 mg12.5 mg/tablet
n = tablets
2.Easy
The prescription is 80 mg. The stock solution contains 200 mg in 5 mL. What volume V do you draw up?
80 mg200 mg/5 mL
V = mL
3.Medium
An ampoule of epinephrine (adrenaline) is labelled 1:1000 (1 mg/mL). The prescription is 0.5 mg IM for anaphylaxis. What volume V do you draw up?
1:10000.5 mg
V = mL
4.Medium
A prefilled syringe of epinephrine (adrenaline) is labelled 1:10 000 (0.1 mg/mL). The prescription is 1 mg IV in cardiac arrest. What volume V do you give?
1:10 0001 mg
V = mL
5.Hard
You must prepare 200 mL of a 2% (w/v) solution from a 25% (w/v) stock solution. What volume of stock V₁ do you need?
C₁ = 25%C₂ = 2%V₂ = 200 mL
V₁ = mL
6.Hard
The prescription is 1800 units of a drug that comes as 10000 units/mL. Draw up the dose in the 1 mL syringe: what volume V do you give?
1800 units10000 units/mL
V = mL
Answer key
- 1. n = 0.5 tablets
- 2. V = 2 mL
- 3. V = 0.5 mL
- 4. V = 10 mL
- 5. V₁ = 16 mL
- 6. V = 0.18 mL
Full step-by-step solutions: practise this topic on examproblems.com.