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Digoxin toxicity — GPhC CRA MCQ

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HardCardiovascular TherapeuticsDigoxin toxicityGPhC CRA

A patient taking tacrolimus after renal transplantation is prescribed clarithromycin for a chest infection. His most recent tacrolimus trough concentration was therapeutic and eGFR is 48 mL/min/1.73 m². What is the safest pharmacy action?

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Correct answer: D — Contact the prescriber urgently about an alternative antibiotic

Clarithromycin strongly inhibits CYP3A4 and can rapidly increase tacrolimus exposure, causing nephrotoxicity and other serious toxicity. The prescription needs urgent prescriber review so that a non-interacting antibiotic can be selected or specialist tacrolimus monitoring and dose adjustment arranged. The pharmacist should not independently alter transplant immunosuppression.

Reference: https://www.pharmacyregulation.org/students-and-trainees/pharmacist-education-and-training/registration-assessment