Hi Carrie,
I am so sorry your Dad is having these horrible problems and hope he will soon be better. I pray he will respond to the chemo and soon be able to have surgery.
When we are taking chemo, food just does not taste good in our mouth. It is most important to keep him hydrated. A drinking straw works miracles! Try cold Ensure with protien, broths, juices, etc.; have him put the straw deep in his mouth and as he sucks on the straw and swallows, the liquid will go directly into his throat....not into his mouth.
I hope this will help your Dad and any others that have the problem of.
Keep a positive attitude, stay strong, have hope and faith for better days ahead.
Prayers and blessings,
B