I have posted before about a drink called Resurgex. The nurse at chemo had given me samples, then I ordered my own over the internet. It comes in a fruit smoothie, van, & choc. flavor. Their Resurgex select has protein and vitamins for people going thru treatment. I still drink them. I blend a yogurt, or fruit in them and they are good. They aren't milky or thick like boost. The website is www.regurgex.com. Maybe look into this. Also does he use a straw? I found this very helpful so I didn't have to taste things too long, just suck it down and get it into the body!! Hope this helps someone. Linda