In "stupid terms" as I say, it's like a microwave. Once you pull the meat out it's still cooking so once we finish rads we are still cooking. All of our problems taken one on one are manageable but when you combine the effects both physical and mental of weeks of nausea, pain, dehydration, constipation and total body weakness most of us reach a critical point when our body is about to give up and that usually occurs 2 to 3 weeks post Tx. Our body has been under extreme attack by the cancer in the first place and then we undergo surgery (some) and a combo of chemo and the maxium amount of rad our body can withstand in a lifetime. Most of us don't help our body by depriving it the water and fuel it needs to meet minimum daily needs much less one under such stress so the outcome is logical to me.

Tell him to get as much water and "food" in his system as he can and hang in there for a few more weeks and he will see progress.