Anti nausea drugs are often seratonin antagonists (decrease the amount of seratonin) which would be bad for depression where you are trying to increase the serotonin. (That's why some antidepressants make you nauseous when you first take them) some anti nausea drugs act locally in the stomach and others act centrally in the brain
Regardless, tripping you are right, I'll see the pharmisist today when I pick up my meds. Thanks - good thinking.