Yeah some formula's suck. I never did well with the tube. In fact every time I tried to use it I vomited - So I gave up and set about sucking up the momentary pain and chugging my formula. I had bilateral radiation, and chemo - so as the rads guy said... there was more fall out from the extra rads. Regardless I felt okay. I mean compared to others. It was horrid, but doable. Maybe try to get him to do a high calorie high protein shake by mouth. They're bland and will hurt like the devil, but if he takes some magic mouthwash just before he drinks it - he should be able to get through it with minimal pain.

Hugs and best of luck.