Common Registration Assessment, Part 1
Clopidogrel tablet strengths and supply counts for the GPhC assessment
Three original practice questions, with the working shown. Read the stated prescription or plan before calculating.
Published 19 October 2026. Independent revision material, not GPhC questions, not for patient care.
The NHS gives the usual adult dose of clopidogrel as 75 mg once a day, using 75 mg tablets.
The NHS also describes a one-off loading dose of 300 mg or 600 mg on the first day in some situations, after which the daily 75 mg dose continues.
Each question fixes the values needed for its arithmetic. Write the unit beside every step and keep a loading day separate from the days that follow. All prescriptions and patients here are fictional; these are revision materials, not for patient care.
The method
- Identify the exact dose, tablet strength and schedule supplied in the question.
- Calculate one dose first; divide prescribed mg by mg per tablet.
- Keep a first-day loading dose separate from the once-daily doses that follow.
- Scale to the stated duration only when a supply is requested.
- Check the tablet count is a whole number 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 clopidogrel 75 mg once a day using 75 mg tablets. How many tablets are needed for 28 days?
Show the answer
Answer: 28 tablets
Working: 75 ÷ 75 = 1 tablet a day. 1 × 28 = 28 tablets.
Question 2
A fictional plan specifies a clopidogrel loading dose of 300 mg on day 1 using 75 mg tablets, then 75 mg once a day. How many tablets are needed for day 1 plus the next 27 days?
Show the answer
Answer: 31 tablets
Working: Day 1: 300 ÷ 75 = 4 tablets. Then 75 ÷ 75 = 1 tablet a day for 27 days = 27 tablets. 4 + 27 = 31 tablets.
Question 3
A fictional prescription specifies clopidogrel 75 mg once a day using 75 mg tablets. How many tablets are needed for a 90 day supply?
Show the answer
Answer: 90 tablets
Working: 75 ÷ 75 = 1 tablet a day. 1 × 90 = 90 tablets.
Exam approach
A loading dose is one different day, not a new daily dose. Calculate it separately, then count the ordinary days.
Where marks are lost
- Applying the loading dose to every day of the supply.
- Forgetting to add the loading day into the total.
- Reporting the number of days instead of the number of tablets.
Frequently asked questions
Are these official assessment questions?
No. They are original revision exercises, not official GPhC questions and not for patient care.
Do I need to memorise the strengths?
The exercise supplies them. In the assessment, read any given product information exactly as written.
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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