We use Glutathione and NAC. In combination with this - and other supplements of course, like probiotics - we use a mixture of dried herbal extracts. These extracts are very important and works well with GSH etc.
The herbs are: Thyme, mullein, turmeric, schisandra and goldenseal.
Also she gets Japanese matcha tea on a daily basis.
Amounts and regularity are important factors, and also to accept that it is the combination and interaction of the different supplements that do the trick.
I have tried isopathic and homeopathic remedies for staph. with no effect. And it is the same with gotu kola, grapefruit extract, Cat's claw, Echinacea, licorice and other many herbs.
The remedies that work for "normal" children/adults don't work for our CF-child and vice versa!
As for herbs, one must be very careful, as many herbs can make the condition worse by producing more mucus. This goes for fenugreek, licorice, common plantain and many other herbs traditionally used for mucus membrane...