What are radio protectants, and can they decrease my side effects from radiation therapy?

Yes: Amifostine protects good tissue during radiation in certain cases such as head and neck cancers. It has not been shown to also protect the cancer which is a good thing but there is the concern of using protectants while you are trying to kill cancer. But we use radiosensitzers more often than protectants because we want to have a better effect in killing the cancer.

See below: Radioprotectants are really only useful if they offer differential radioprotection to normal tissues and not tumor cells. That's really the problem. A general radioprotectant would benefit the cancer cells as much as normal cells thus you haven't changed the therapeutic ratio.

WR-2721: Was developed by the army for b-52 pilots. It didn't cross to protect the brain, and turns out to be too toxic for most clinical use (hypotension and vomiting). It was differentially, and time-related taken up by normal tissues more than tumors. See amifostine, or ethiofos. As a product, it is hard to use and quite expensive.