I use the home made recipe. You use one qt. of water, 2-3 tsp. of 'Kosher' or "pickling' salt, and 1 tsp. of baking soda. You mix it in, put it in a GLASS jar and you have to make a new solution every week. This has been recomended by my CF dctors forever, but I just recently started using it again. Its supposed to be really good because (a) its cheap, (b) not a drug and (c) there are no preservatives (which is why you have to make a new one every week).
I squirt it up my nose with a nasal aspirator (which is what ppl use for babies), and then it usually drips out or down the throat. Then I blow my nose numerous times. The salt water helps to break the mucus free, and thus gets it all out. It also helps to coat the nasal passages, so that germs arent as able to get there. Its such a great thing and I have noticed a huge difference in the past few weeks.
My theory, at least for my case, was that after the salt solution started to work, so after a week, I began to cough up a lot of junk. I dont know if this junk was from my lungs, or my nose, but I am leaning towards m y nose. I think that the salt solution, started to get so high up my in my nasals, that it just broke all that old mucus loose. I have noticed a huge difference, in that I can breathe easier, and my nose is less dry and I just feel overall better.