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St John's wort interaction — GPhC CRA MCQ

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ModerateCNS TherapeuticsSt John's wort interactionGPhC CRA

A 40-year-old man taking sertraline asks to buy St John's wort because his mood remains low. What is the most important interaction to flag?

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Correct answer: D — St John's wort with sertraline can increase serotonergic toxicity risk

St John's wort can interact with antidepressants and increase serotonergic adverse effects. It also induces enzymes and interacts with many medicines, reducing effectiveness of some drugs. The patient should be referred to the prescriber for review of depression treatment.

Reference: BNF