skip to main content

CD Schedule 4 prescription requirements — GPhC CRA MCQ

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

HardPharmacy LawCD Schedule 4 prescription requirementsGPhC CRA

A patient established on lamotrigine 200 mg daily, with no valproate or enzyme-inducing medicines, has taken none for 10 days and asks to resume the full maintenance dose. They stopped because they ran out, not because of a rash. What is the safest response?

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

Reveal the answer and explanation

Correct answer: A — Contact the prescriber for re-titration rather than restarting the full maintenance dose

After a sufficiently long interruption, lamotrigine should generally be re-escalated using the appropriate titration schedule because restarting at a high dose increases the risk of serious rash. Ten days is long enough to require prescriber review rather than automatic resumption of 200 mg. Prior tolerance, an antihistamine or a loading dose does not remove the rash risk, and valproate cannot be substituted milligram-for-milligram and would alter lamotrigine pharmacokinetics.

Reference: Lamotrigine 200 mg tablets SmPC: https://www.medicines.org.uk/emc/product/4740/smpc