Hello Lynn, sorry the side effects have caught up with you. Has the Magic Mouthwash been prescribed for you yet? Rather than rinsing my entire mouth I found that using a cue tip and applying the medicine directly to the painful area worked best for me.
The only protein drink I could tolerate was Fairlife Chocolate and have to admit I wasn't too fond of this either.
Oatmeal (one half cup with cup of water) with honey (spoonful), raisins, Cinnamon and then milk to improve consistency became my go-to food when side effects were at their worst.
My OPDIVO immunotherapy infusions every two weeks haven't produced any side effects as of yet, fingers crossed.
Hang in there and keep your positive attitude, spring is coming and the walks in the woods are something to look forward to!