Dad's Side Effects

My 82 year old father was recently diagnosed with Colorectal cancer in October of this year. Treatment began with Folfox, taking the pump home for two days, going back two weeks. He was in pretty good shape at the beginning, before treatment, bowling three days a week, hunting, fishing, outside all the time with his lab Sandy. The first two treatments were tolerable, the third kicked some major a--. Major loss of weight, hard to eat with severe heartburn, hiccups. nothing seemed to help. Then shingles developed in his mouth and throat. At first we thought it was a severe sore throat, but ended up in the hospital ER after a few days of not eating or drinking much. He got out on Thursday of this week. Had IV antibiotics in hospital, now finishing antibiotics at home. He has severe burning from his nose which runs constantly and on his buttocks from having diarrhea. Does anyone else have these side effects and what do you suggest I can do to help him? I have given him A & D ointment and it helps somewhat, but not enough. I have read all your posts since October and I appreciate your knowledge and courage in fighting this disease. Thank you for any help you can provide.