Common Registration Assessment, Part 1
Montelukast tablets, chewables and granules by age for the GPhC assessment
Three original practice questions, with the working shown. Read the stated prescription or plan before calculating.
Published 18 October 2026. Independent revision material, not GPhC questions, not for patient care.
The NHS lists montelukast as 10 mg non-chewable tablets, chewable tablets of 5 mg or 4 mg, and granules in sachets of 4 mg.
The usual dose is one 10 mg tablet once a day for adults and children aged 15 and over, one 5 mg chewable tablet once a day for children aged 6 to 14, and 4 mg once a day for children from 6 months to 5 years, as granules or a chewable tablet for children over 2. Never take more than one dose a day.
Each question fixes the values needed for its arithmetic. Write the unit beside every step and match the form to the stated age band. All prescriptions and patients here are fictional; these are revision materials, not for patient care.
The method
- Identify the age band and the dose form supplied in the question.
- Match the age band to the stated strength: 10 mg, 5 mg or 4 mg.
- Count one unit per day; montelukast is a once-daily medicine.
- Scale to the stated duration only when a supply is requested.
- Check the total against one dose a day 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 montelukast 10 mg once a day for an adult using 10 mg tablets. How many tablets are needed for 28 days?
Show the answer
Answer: 28 tablets
Working: 10 ÷ 10 = 1 tablet a day. 1 × 28 = 28 tablets.
Question 2
A fictional prescription specifies montelukast for a child aged 8, one 5 mg chewable tablet once a day. How many chewable tablets are needed for 30 days?
Show the answer
Answer: 30 chewable tablets
Working: One 5 mg chewable tablet a day. 1 × 30 = 30 chewable tablets.
Question 3
A fictional prescription specifies montelukast granules for a child aged 3, one 4 mg sachet once a day. How many sachets are needed for 30 days, and what is the total dose over that time?
Show the answer
Answer: 30 sachets, 120 mg in total
Working: One 4 mg sachet a day. 1 × 30 = 30 sachets. 4 × 30 = 120 mg.
Exam approach
Age band questions are matching exercises before they are arithmetic. Fix the strength from the band first, then the count is one unit per day multiplied by the days.
Where marks are lost
- Giving the adult 10 mg tablet to a child in the 6 to 14 band instead of the 5 mg chewable.
- Counting two doses a day; the NHS states never more than one dose a day.
- Reporting a mg total when the question asks for the number of sachets or 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 age bands?
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
- NHS: How and when to take montelukast
- 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.