Michael,
I must have mentioned this before but Zofran is really only effective for the first 3-5 days after a chemo Tx then you must switch to another anti-emetic.

Towards the end and after Tx, I puked so much I polished my teeth like glass from all of the acid. It's a miserable experience and I hope yours isn't as severe but I am living proof that you can survive this hell.

I never thought that I would use the compazine suppositories but I was really grateful I had them and went through several boxes much to my surprise. There are other antiemetics, as well, that are as effective as Zofran. Are you taking antacids? that may help as well.

Practically anything can cause the nausea, constipation, narcotics, chemo, radiation, mucositus, inflamed stomach lining, etc.

Be sure to keep hydrated especially after you get sick.