Common Registration Assessment, Part 1

Hydroxyzine divided daily doses and daily dose maximums for the GPhC assessment

Three original practice questions, with the working shown. Read the stated prescription or plan before calculating.

Published 7 November 2026. Independent revision material, not GPhC questions, not for patient care.

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The manufacturer's UK product information for hydroxyzine 10 mg film-coated tablets states that for anxiety in adults the dose is 50 to 100 mg daily in divided doses, and that for pruritus the starting dose is 25 mg at night, increasing as necessary to 25 mg three or four times daily.

The same information states that the maximum daily dose is 100 mg per day in adults and children over 40 kg, 50 mg per day in the elderly, and 2 mg/kg/day in children up to 40 kg.

It also states that from 6 months to 6 years the dose is 5 to 15 mg daily in divided doses, and that for children over 6 years the dose starts at 15 to 25 mg and may be increased to 50 to 100 mg daily in divided doses, adjusted according to the child's weight.

Each question fixes the values needed for its arithmetic. Write the unit beside every step and distinguish a single dose from a daily total or a supply period. All prescriptions and patients here are fictional; these are revision materials, not for patient care.

The method

  1. Identify the stated single dose and the number of doses each day.
  2. Multiply the single dose by the daily frequency for the daily total, and compare it with the stated maximum.
  3. Divide the daily dose by the tablet strength to count tablets per day.
  4. Keep milligrams, mg per kg and tablets separate; convert only when the question asks.

Three practice questions

Work each one on paper first, then open the answer. All patients and prescriptions are fictional.

Question 1

A fictional adult takes hydroxyzine 25 mg four times daily for pruritus. How many milligrams is this each day, and does it reach the stated adult maximum?

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Answer: 100 mg, which is the maximum

Working: 25 mg x 4 doses = 100 mg each day. The stated maximum for adults is 100 mg per day, so this reaches it exactly.

Question 2

A fictional child weighs 20 kg. Using the stated maximum of 2 mg/kg/day for children up to 40 kg, what is the maximum daily dose?

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Answer: 40 mg

Working: 2 mg x 20 kg = 40 mg per day.

Question 3

A fictional elderly patient takes the stated elderly maximum of 50 mg per day in two divided doses using 25 mg tablets. How many tablets is this each day?

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Answer: 2 tablets

Working: 50 mg / 25 mg per tablet = 2 tablets each day, one tablet in each divided dose.

eMC SmPC: Hydroxyzine 10 mg film-coated tablets

https://www.medicines.org.uk/emc/product/100997/smpc

Where marks are lost

  • Applying the adult 100 mg maximum to a child whose maximum is set by weight in mg per kg per day.
  • Treating 25 mg four times daily as exceeding the adult maximum when it equals it exactly.
  • Dropping one of the divided doses when converting a daily maximum into a tablet count.

Frequently asked questions

Are these official assessment questions?

No. They are original revision exercises, not official GPhC questions and not for patient care.

Does this calculation decide a real hydroxyzine dose?

No. Follow the stated prescription in the exercise. Real dosing uses the lowest effective dose for the shortest duration, with lower maximums in elderly patients and weight-based maximums in children.

How should I check the answer?

Check the requested unit, then confirm the daily total against the stated maximum for the patient's group.

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.

More calculation topics

See also the formula sheet, the eight sample questions and the approved calculator page.