Hello @jared237, While you wait for suggestions from members with experience, I thought you might want to scan through the discussions and comments by members on your question. Here's the link with the discussions and comments - https://connect.mayoclinic.org/search/comments/?search=Nausea%20from%20Radiation.

Here are some suggestions from the following research article:
"Try cold foods such as popsicles, pudding, yogurt, and gelatin. Try bland, starchy foods such as toast, rice, plain pasta, crackers, and pretzels. Foods and beverages with ginger, such as ginger ale and ginger tea, may also ease nausea and vomiting."
-- Nausea and Vomiting and Cancer Treatment – Side Effects:
https://www.cancer.gov/about-cancer/treatment/side-effects/nausea-vomiting
Have you discussed the side effects with your doctor or care team to see if they may have some specific suggestions related to your treatment?