Breast cancer radiation side affect?

My grandmother recently got breast cancer and had her breasts removed. After the chemotherapy, she started radaiation. I am not sure what week she is in, but she is 60 years old. Lately she has been telling me she has a very sore throat. So sore that she cannot even swallow her saliva. Does anyone have any remedies or something that wil help her feel just a little better? Just enought so she can eat food? She lives in a different country, so medications wont do much good. Thanks!