Why is he not trying to eat whatever he feels like? Did his docs say not to eat by mouth? That would be unusual.

As Margaret says the first few weeks post Tx are usually by far the worst for most of us and also remember that his recovery will be very slow lasting the better part of 2 years. For me I didn't think I was going to live until the 3rd week post Tx. I called it "finally walking out of a dark tunnel". Even then I had more bad days than good ones and slowly the good days began to out number the bad days until eventually the bad days went away but this was months after my Tx had ended. I felt as weak as a new born kitten for a long time but again slowly all will return to an almost pre normal state. My taste and saliva took 15 months before I was satisfied and now I guess I'm around 90 to 95% pre normal.

Another very important thing to keep in mind is that we all can react differently so tell him he will recover at his own pace but I do know that I felt better when I was consuming at least 3000 calories a day.