Common Registration Assessment, Part 1
Atorvastatin tablet strengths and daily doses 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.
The NHS lists atorvastatin as 10 mg, 20 mg, 30 mg, 40 mg, 60 mg and 80 mg tablets, plus 10 mg and 20 mg chewable tablets. The usual adult dose is between 10 mg and 80 mg a day.
Doses that combine strengths, such as 70 mg, need fewest-tablet reasoning across the six strengths.
Each question fixes the values needed for its arithmetic. Write the unit beside every step and keep a single dose separate from a supply. All prescriptions and patients here are fictional; these are revision materials, not for patient care.
The method
- Identify the exact strengths available and the dose supplied in the question.
- Calculate one dose first; for tablets divide prescribed mg by mg per tablet.
- For combined strengths, start with the largest tablet that does not overshoot.
- Scale to the stated duration only when a total supply is requested.
- Check the final count against the available strengths.
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 atorvastatin 40 mg once a day. How many 40 mg tablets are needed for 90 days?
Show the answer
Answer: 90 tablets
Working: One 40 mg tablet a day for 90 days: 1 × 90 = 90 tablets.
Question 2
A fictional prescription specifies atorvastatin 70 mg once a day. Using the available tablet strengths, what is the fewest number of tablets for one dose?
Show the answer
Answer: 2 tablets
Working: One 40 mg tablet plus one 30 mg tablet: 40 + 30 = 70 mg. No single tablet makes 70 mg, and no other pair uses fewer.
Question 3
A fictional prescription specifies atorvastatin 20 mg once a day using the chewable tablets. How many chewable tablets are needed for 28 days?
Show the answer
Answer: 28 tablets
Working: One 20 mg chewable tablet a day for 28 days: 1 × 28 = 28 tablets.
Exam approach
Fewest-tablet questions are greedy: largest strength first, then the remainder. Atorvastatin has six strengths, so check 60 and 30 before smaller splits.
Where marks are lost
- Forgetting that 30 mg and 60 mg tablets exist when combining strengths.
- Mixing chewable and standard tablets in one count.
- 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.
How do I find the fewest tablets?
Take the largest strength that does not overshoot, then repeat on the remainder.
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 atorvastatin
- 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.