A patient diagnosed with major depressive disorder tells the nurse, "I want to try supplementing my selective serotonin reuptake inhibitor (SSRI) with St. John's wort." Which action should the nurse take first?

A) Advise the patient of the danger of serotonin syndrome.
B) Suggest that aromatherapy may produce better results.
C) Assess the patient for depression and risk for suicide.
D) Suggest the patient decrease the antidepressant dose.

Research has suggested that St. John's wort is a mild inhibitor of serotonin reuptake and could lead to serotonin syndrome; this risk is increased if the patient is taking other medications that increase serotonin activity. Assessing the depression would be a secondary intervention. Aromatherapy has not been shown to be an effective adjunct or treatment for depression. Although a dosage reduction in her SSRI medication might reduce the risk of serotonin syndrome, this intervention is not in the nurse's scope of practice.