Opioid-induced constipation — GPhC CRA MCQ

Instant feedback + full explanation. One question, done properly.

HardGastrointestinal TherapeuticsOpioid-induced constipationGPhC CRA

A patient with cancer pain takes modified-release oral morphine 60 mg every 12 hours. The local palliative protocol sets immediate-release breakthrough morphine at one-sixth of the regular 24-hour dose. What breakthrough dose does that protocol generate?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: B — 20 mg

The regular 24-hour dose is 60 × 2 = 120 mg; one-sixth is 20 mg, making Option B correct. Option E uses one-twelfth. Option D uses one-tenth, which lies within some guideline ranges but not the protocol specified in this stem. Option C divides by four. Option A uses one entire modified-release dose rather than a breakthrough fraction.

Reference: Scottish Palliative Care Guidelines: https://www.rightdecisions.scot.nhs.uk/scottish-palliative-care-guidelines/scottish-palliative-care-guidelines/symptoms/pain/pain-management/; GPhC framework: https://assets.pharmacyregulation.org/files/2025-09/Common-Registration-Assessment-framework-for-sittings-in-2026.pdf