A patient who received a renal transplant three months ago is readmitted to the acute care unit with signs of graft rejection.During the patient’s history taking, the nurse finds out that the patient has been self-administering St. John’s Wort, an herbal preparation, on a friend’s advice.What information is most significant about this finding?

Choice A rationaleSt. John’s Wort is known to interact with many prescription drugs, including cyclosporine, a medication often given to transplant patients to prevent organ rejection. St. John’s Wort can decrease plasma concentrations of cyclosporine, thus endangering the success of organ transplantations.Choice B rationaleThere is no evidence to suggest that consumption of St. John’s Wort can reduce the patient’s sodium intake.Choice C rationaleAdding the herb does not decrease the need for corticosteroids. In fact, it can interact with many medications and cause serious complications.Choice D rationaleWhile St. John’s Wort is often used to treat depression, in the context of a patient who has undergone a renal transplant, the most significant information is its potential to interact with cyclosporine and endanger the success of the transplant.