How much vomiting can you expect during chemotherapy?

Depends. Some chemotherapy drugs cause more nausea than others. There are many good drugs today that can decrease the amount of nausea and work for days at a time. Besides the medicines to decrease nausea, other things that help are small frequent high protein meals instead of large meals.
It depends. Different types of chemotherapy have different potentials for causing what we refernto as emetogenesis. We now routinely employ very effectivemdrugsnto prevent nausea and vomiting so it is not nearly as big amproblem as it once was.