Hi, Carrie, this is an issue I struggle with, too, and I know your struggle is harder. I've been doing some reading which seems to indicate that cystic fibrosis, though we refer to it as one disease, is actually as individual as your DNA. More and more, researchers are finding that the "phenotype" (that is, how CF affects you) has as much to do with the rest of your DNA as the specific CF mutation you have. For example, they have found a couple of "modifier alleles" that are associated with early PA acquisition. Other modifier alleles cause greater susceptibility to fibrosis. Others are linked to liver problems. I guess the upshot is that sometimes what will work and how it will work is unknowable beforehand because our CF is just so individualized. But I still keep wondering about this issue so much, for there is so much heartache in it.