Common Registration Assessment, Part 1
Amlodipine 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 17 October 2026. Independent revision material, not GPhC questions, not for patient care.
The NHS lists amlodipine as 5 mg and 10 mg tablets. The liquid comes in two strengths: one with 5 mg in 5 mL and one with 10 mg in 5 mL.
The usual starting dose is 5 mg once a day, which may be increased to 10 mg once a day. Treatment is usually long term, so supply calculations over 28 days are common.
Each question fixes the values needed for its arithmetic. Write the unit beside every step and distinguish a single dose from a 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 divide prescribed mg by mg per tablet.
- Scale to the stated duration only when a total supply is requested.
- Keep the two liquid strengths separate; they differ by a factor of two.
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 amlodipine 10 mg once a day using 5 mg tablets. How many tablets are needed for 28 days?
Show the answer
Answer: 56 tablets
Working: 10 ÷ 5 = 2 tablets a day. 2 × 28 = 56 tablets.
Question 2
A fictional prescription specifies amlodipine 2.5 mg once a day using the liquid with 5 mg in 5 mL. What volume is one dose?
Show the answer
Answer: 2.5 mL
Working: 5 mg in 5 mL is 1 mg per mL. 2.5 ÷ 1 = 2.5 mL.
Question 3
A fictional prescription specifies amlodipine 5 mg once a day, changed from tablets to the liquid with 10 mg in 5 mL. What volume is one dose?
Show the answer
Answer: 2.5 mL
Working: 10 mg in 5 mL is 2 mg per mL. 5 ÷ 2 = 2.5 mL. The same mg dose is half the volume because this liquid is twice as concentrated.
Exam approach
Convert the liquid to mg per mL before anything else. The two amlodipine liquids differ by a factor of two, and the question's label decides which one applies.
Where marks are lost
- Assuming both liquids have the same concentration because both use 5 mL.
- Reporting a supply when the question asks for one dose.
- 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 do the two liquids matter?
Both are measured in 5 mL but one is twice as concentrated, so the same dose needs half the volume.
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 amlodipine
- 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.