16th May 2025

A 60-year-old woman who received a liver transplant 6 months ago presents to the emergency department with a fever and sore throat.

A 60-year-old woman who received a liver transplant 6 months ago presents to the emergency department with a fever and sore throat. Her immunosuppressive regimen for her transplant includes tacrolimus. She was recently started on an oral course of fluconazole for genital candidiasis. Her drug history also includes felodipine, indapamide, candesartan and metformin. On examination her heart rate is 99/min, her blood pressure is 98/72 mmHg, and her temperature is 39.4. When examining her throat there is significant pharyngitis. An ECG was performed which showed a QTc interval of 480ms. Her laboratory tests show a Hb of 98, WCC of 3.2 x109/L, platelets 112, sodium 114mmol/L, potassium 5.7mmol/L, creatinine 170micromol/L. Which of the following medications is the most likely cause of her investigation findings?

Select the SINGLE most appropriate option from the list below. Select ONE option only.