Hi run4peach1,
Yes of cause your father needs Vancomycin.
Nutrition is a very serious problem for most cancer patients. It is difficult to gain weight when you feel ill.
When I got the dx myelofibrosis during 15 months I read that the patients often got very thin so I decided to keep the weight I had at dx (though it is a little too high). I control my weigt every day and eat more if I am loosing weight for example when I get my Desferal infusion for 4 days with transfusion.
Very good that your father will get a feeding tube so he will receive everything he needs
! Perhaps he can try nutritional drinks and find some that he can tolerate. I hope this link is OK - there are many kinds of nutritional drinks.
http://www.nutritionincancer.co.uk/en/forti-range.html
Kind regards
Birgitta-A