Common Registration Assessment, Part 1
Gliclazide standard and slow-release tablets for the GPhC assessment
Three original practice questions, with the working shown. Read the stated prescription or plan before calculating.
Published 17 October 2026. Independent revision material, not GPhC questions, not for patient care.
Standard gliclazide tablets come in 40 mg and 80 mg strengths, and the slow-release (modified-release) tablets come as 30 mg and 60 mg, as listed in the BNF.
The NHS states the maximum daily dose for standard gliclazide is 320 mg, and that doses above 160 mg a day should be divided into 2 equal doses. For slow-release gliclazide the maximum daily dose is 120 mg, usually one dose in the morning.
Each question fixes the values needed for its arithmetic. Write the unit beside every step and keep standard and slow-release tablets as different products. All prescriptions and patients here are fictional; these are revision materials, not for patient care.
The method
- Identify whether the question uses standard or slow-release tablets and the stated strengths.
- Calculate the daily total, then divide by mg per tablet.
- Split into 2 equal doses only when the stated daily dose is above the stated threshold.
- Scale to the stated duration only when a total supply is requested.
- Check any dose against the stated maximum before reporting 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 standard gliclazide 160 mg a day using 80 mg tablets. How many tablets is one day?
Show the answer
Answer: 2 tablets
Working: 160 ÷ 80 = 2 tablets. The daily dose is not above 160 mg, so no split is needed.
Question 2
A fictional prescription specifies standard gliclazide 240 mg a day, divided into 2 equal doses, using a supply of 80 mg and 40 mg tablets. What is the fewest number of whole tablets for each dose, and how many tablets is one day?
Show the answer
Answer: 2 tablets per dose, 4 tablets a day
Working: 240 ÷ 2 = 120 mg per dose. Each dose: 120 ÷ 80 = 1.5, so one 80 mg plus one 40 mg tablet = 2 tablets per dose. Per day: 2 doses × 2 tablets = 4 tablets (two 80 mg plus two 40 mg).
Question 3
A fictional prescription specifies slow-release gliclazide 90 mg once a day using 60 mg and 30 mg modified-release tablets. What is the fewest number of tablets for one dose?
Show the answer
Answer: 2 tablets
Working: One 60 mg plus one 30 mg modified-release tablet: 60 + 30 = 90 mg.
Exam approach
Name the product type first. Standard gliclazide splits above 160 mg a day; slow-release is usually one morning dose with its own 120 mg maximum.
Where marks are lost
- Mixing standard and slow-release strengths in one count.
- Splitting the dose when the stated daily dose does not require it.
- 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.
Why are the two types kept separate?
Standard and slow-release tablets have different strengths and daily schedules, so they are never interchangeable in a calculation.
How should I check the answer?
Check the requested unit, then work backwards from the quantity to the stated dose and duration.
Sources
- NHS: How and when to take gliclazide
- BNF: Gliclazide medicinal forms
- GPhC, Common Registration Assessment specification and permitted items for 2026
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.