After 6 Months of Taking Imipramine (Tofranil) for Depressive Symptoms

After 6 months of taking imipramine (Tofranil) for depressive symptoms, a client complains that the medication doesn't seem as effective as before. Which question should the nurse ask to determine the cause of this problem?

A) "Are you consuming foods high in tyramine?"
B) "How many packs of cigarettes do you smoke daily?"
C) "Do you drink any alcohol?"
D) "Are you taking St. John's wort?"