One of the most common side effects of radiation we all seem to get is increased thick mucus or perhaps a better way to describe it is a decrease in thin saliva production making the thick mucus more apparent. I too was left with more thick mucus than thin but mine is more of a nuisance than what you are experiencing. Not sure if there is a cure but I do know that some things make mine worse, like milk which I love and some things seem to make it less noticeable, like citrus, especially oranges. Since we all can be damaged and therefore affected differently you might want to at least try to ID those incidents which make more mucus and avoid them. That is, of course, after you have exhausted any medically related causes.

I also have more of a sweet taste but again it doesn't bother me. I taste sweet in almost anything now. Just last night I was commenting on how I could taste a sweetness in my baked potato with salt and butter.