Hi Zara,
I believe that herbs, vitamins, and other supplemental therapies have a place in treating my own CF. One of the problems is according to my doctor (who does recommend certain supplements etc. for her patients) is that compared to allopathic medicine there aren't known dosages dues to lack of testing. Plus the purity is questionable. She is always reading the research so she can help her patients, find appropriate and safe alternatives. And she recommends always buying supplements that have independent testing and are standardized.
You are new here and it would be hard to describe all the things that I do in one post. But you did ask specific questions about GHS. I was in a serious decline 11 years ago, constant pseudomonas, staph, MAC infections, etc., as low as 32% FEV1, 96 pounds. BAD. Under this doctor, the cycle of infections stopped (with occasional exercerbations) FEV1 climbed back to 54% (limited by much prior lung damage).
Then in 2004, I was exposed to smoke in my house from the LA fires (in MY neighborhood) and I declined horribly again. I did all the things I did before --controlling inflammation and the asthma component of CF -- with lifestyle changes and allergy control) and I added 3 things. Tumeric (curcumin), NAC capsules, and hypertonic saline and the bad phase ended. In the last few cultures, pseudomonas isn't even being picked up which is amazing. The pseudomonas will never be gone, but the levels must be pretty low (I used to have multiple strains 3 and 4 plus. Also the MRSA changed to staph and now that's not being picked up either.
Tumeric and NAC are currently being studied by the Cystic Fibrosis Foundation and I thought if it is good enough for them to test, there must be something there.
I don't believe just adding supplements is enough. People get exacerbations due in part to allergy and chemical triggers. This causes inflammation, the airways swell, trapping the mucus. I have learned that exacerbation is frequently due to inflammation and for me usually can treat it without antibiotics (under my doctor's guidance), but if the inflammation isn't reduced, there is the danger of it turning into infection (and pneumonia) because the trapped mucus cannot get out.