From:
http://bioadvantexstore.com/usdstore...61f8f36a9cdc96
"
NAC is an antioxidant that must be processed in an extremely dry environment with extremely limited exposure to air. If it becomes oxidized to any degree, then it becomes destabilized and therapeutically ineffective. Unfortunately, some OTC NAC supplements sold on the market today are not manufactured under such strictly controlled environments due to the enormous associated control costs. As a result, these products often have little or no active NAC in them, despite labeling to the contrary.
This is precisely why BioAdvantex takes great care in diligently manufacturing PharmaNAC according to strict pharmaceutical standards. Special care is required to ensure that the components of each
PharmaNAC tablet do not react during manufacture or within the compressed tablet following manufacture. In fact,
each PharmaNAC tablet is individually wrapped in a special 4-layer (paper/plastic/foil plastic) air-tight material to prevent moisture and air from destabilizing and degrading the NAC (unlike other NAC products that loosely package numerous quantities of NAC capsules in a plastic bottle openly exposed to air). Our European GMP-compliant manufacturing process secures consistent quality, content uniformity, and stability in each and every 900mg effervescent tablet."
*red mine
I know this is from the site selling the product, but it was the most concise explanation I could find. They use PharmaNac in the drug studies, if that helps any

.
And here is a link to the Mucomyst page at Drugs.com:
http://www.drugs.com/pro/mucomyst.html
(It's pretty long, but you can scroll through and find what is pertinant for lung issues/mucus thinning

)
Here is a pic of how Mucomyst is distributed (as you can see, pretty strict in oxygen exposure per dose too):
http://www.webmd.com/drugs/image.asp...502&cb=mywebmd
Other than asking about the packaging process, I don't know how to tell. I do know that these are the only 2 that the people who have looked into NAC in the CF community use.
I wish I could help you more, but I take the PharmaNac because it's the one used in the drug studies, and am considering using the Mucomyst instead because it's a good bit cheaper (though I hear you have to mix it with something like Grapico to get it down, lol). I've never used the Mucomyst in a neb, though I would like to (I'm fairly stable, and my doctor is going with the "if it ain't broke, don't fix it" route right now

). In a nutshell, I use the ones the medical community recommends.

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