Common Registration Assessment, Part 1
Furosemide tablet and liquid strengths for the GPhC assessment
Three original practice questions, with the working shown. Read the stated prescription or plan before calculating.
Published 16 October 2026. Independent revision material, not GPhC questions, not for patient care.
The NHS lists furosemide tablets of 20 mg, 40 mg and 500 mg, and liquid strengths of 20 mg, 40 mg or 50 mg in every 5 mL. The usual adult dose is 20 mg to 120 mg a day for heart failure or oedema and 40 mg to 80 mg a day for high blood pressure.
A strength named per 5 mL converts to a per-mL figure before any volume is calculated. Doses are usually lower for people over 65, and only the supplied strength belongs in the working.
Each question fixes the values needed for its arithmetic. Write the unit beside every step and distinguish a single dose from a daily total or course supply. All prescriptions and patients here are fictional; these are revision materials, not for patient care.
The method
- Identify the exact formulation, strength, dose and frequency supplied in the question.
- Convert an X mg/5 mL strength to mg/mL if a dose-to-volume conversion is needed.
- Calculate one dose first; for tablets or capsules divide prescribed mg by mg per unit.
- Scale to the stated frequency and duration only when a total quantity is requested.
- Apply whole-container or complete-day rounding only if the question specifies it.
Three practice questions
Work each one on paper first, then open the answer. All patients and prescriptions are fictional.
Question 1
A fictional prescription specifies furosemide 80 mg once daily, using 40 mg tablets. How many tablets make one dose?
Show the answer
Answer: 2 tablets
Working: 80 ÷ 40 = 2 tablets.
Question 2
A fictional dose is furosemide 60 mg, using the liquid containing 20 mg in 5 mL. What volume is one dose?
Show the answer
Answer: 15 mL
Working: 60 ÷ 20 × 5 = 15 mL.
Question 3
A fictional dose is furosemide 40 mg, using the liquid containing 50 mg in 5 mL. What volume is one dose?
Show the answer
Answer: 4 mL
Working: 40 ÷ 50 × 5 = 4 mL. The 20 mg/5 mL liquid would need 10 mL for the same dose, so the label matters.
NHS: How and when to take furosemide
https://www.nhs.uk/medicines/furosemide/how-and-when-to-take-furosemide/
Where marks are lost
- Using a remembered strength or schedule instead of the stated product.
- Reporting a daily total when the question asks for one dose or the course.
- Treating arithmetic as evidence that a real prescription is clinically suitable.
Frequently asked questions
Are these official assessment questions?
No. They are original revision exercises, not official GPhC questions and not for patient care.
Can a quantity calculation justify a formulation switch?
No. Follow the formulation and prescription in the exercise. Real switches and dose changes need clinical checks.
How should I check the answer?
Check the requested unit, then work backwards from the quantity to the stated dose and duration.
Sources
The questions above are original and use fictional patients and prescriptions. PreRegExamPrep is not affiliated with or endorsed by the General Pharmaceutical Council.
Practise until the method is automatic
Try 15 free questions with worked answers. No sign-up required.
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See also the formula sheet, the eight sample questions and the approved calculator page.