For the mouth sores, you can also use flat club soda. He can swallow this too and may help the throat heal. If the regular club soda burns his mouth, see if you can get the low sodium club soda. Club soda works in the same way as the baking soda Christine mentioned in her posts. You have the advantage of not having to make a fresh batch everyday.

Gloria
She stood in the storm, and when the wind did not blow her way, she adjusted her sails... Elizabeth Edwards

Wife to John,dx 10/2012, BOT, HPV+, T3N2MO, RAD 70 gy,Cisplatinx2 , PEG in Dec 6, 2012, dx dvt in both legs after second chemo session, Apr 03/13 NED, July 2013 met to lungs, Phase 1 immunotherapy trial Jan 18/14 to July/14. Taxol/carboplatin July/14. Esophagus re-opened Oct 14. PEG out April 8, 2015. Phase 2 trial of Selinexor April to July 2015. At peace Jan 15, 2016.