Metaclopramide is very effective on nausea and vomiting resulting from chemotherapy. For me as a big bloke, it has the great advantage of allowing an above standard dose relating to body weight, whereas the hospital standard of Domperidone is not variable in this way, and wears out after about five hours in my case. They do work differently and you may find after taking the Oncologist's advice that a different drug will give relief. On the other hand, the symptoms you describe, if resulting from a bug, would not be amenable to these sorts of medications, I imagine.
I would seek advice quickly.
AC