My son also had his radiation treatments stopped for a week when the effects got so bad and he just announced one morning he was not going to go. I really worried about his missing his radiation appointment, but luckily he also had a doctor's appointment the same day so I was able to convince him to let the doctor check him out and after seeing what his mouth and throat looked like, he gave him a week's break. It seemed to help and he continued on with the treatments and doing fine, now 4 years later.