How much NAC is safe per day

In some of the NAC studies, 600 mg twice a day was the protocol. Of course not everyone is wired the same, so once a day might work fine for you. Besides thinning mucus, NAC is an antioxidant, and it might interfere with bacterial biofilms, making them more vulnerable to antibiotics and immune surveillance. Best wishes.

Thank you, @wolfplanetzero. Yes, I had read that NAC seems to reduce bacterial counts, as well as thin the mucus and work as a powerful antioxidant.

I also read that it helps to protect against liver and hearing damage from the MAC drugs. In fact, I also read that zinc supplementation helps to prevent the hearing loss. The mycobacterium meds that also include those for TB chelate metals, specifically copper and zinc.

It is good to take a well-balanced supplement, in addition to eating a well balanced diet.

The one issue that I have when I take the NAC twice daily is sweating. Body temp is usually about 97, so it is not a fever. When I reduce the NAC to once daily, the sweating decreases, but the twice daily thins the mucus better.

I take 2000 mg orally every day

I need clarification on NAC.
I read about it in this group about a year ago and have been taking it daily every since..
The label states for hair and nails.. am I taking the wrong supplement for thinning mucus?
I also take 1200 mg of Mucinex 2 times a day
Will someone please spell THE NAME of NAC ?

NAC is N Acetyl Cysteine -
Here is what Mount Sinai Hospital in New York has to say:
Acetylcysteine; L-cysteine; N-acetylcysteine; NAC. Cysteine is an amino acid, a building block of proteins that are used throughout the body. When taken as a supplement, it is usually in the form of N-acetyl-L-cysteine (NAC). The body makes this into cysteine and then into glutathione, a powerful antioxidant.
There is, confusingly, another N-Acetyl L-Carnitine, sometimes marketed as NAC, but more properly called L-carnitine. You can read about it on Web MD:
https://www.webmd.com/vitamins/ai/ingredientmono-834/acetyl-l-carnitine
So NAC is an anti-oxidant, and a few studies indicate it also helps to thin mucus. There is no RDA established for it, but many people take one 600mg capsule morning and night.
Sue

Has anyone ever heard of Serrapeptase? https://www.webmd.com/diet/health-benefits-serrapeptase#:~:text=Serrapeptase%2C%20also%20known%20as%20serratiopeptidase,down%20their%20cocoons%20at%20birth.

I had not heard of this, and the link you provided was interesting, so I jumped to my go-to source Google Scholar, and found this extensive 2020 article from the NIH - National Library of Medicine - originally from Biotechnology Reports, a self-publishing journal. Most of the authors are affiliated with the pharmaceutical company which manufactures the product.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7585045/
I found a lot of other articles too which talked about anti-inflammatory effects of the enzyme, potential anti-mucolytic effects, and possible anti-biofilm properties. There are also cautions regarding use with blood thinners, NSAIDs, asthma, etc.

So as with all supplements, be sure to check with (all) health care providers before starting, and buy from a reputable source.
Sue

Yes, my former internist in 2006 prescribed NAC to all of her adult patients during flu season, even back then. It is also known to help with insulin resistance and other issues.

People who have asthma are at risk for having bronchospasm when they use NAC, so they need to exercise caution to see how it affects them

Thank you, Sue.

Thank you for the info about bronchospasm, asthma and NAC