Functionality

• N-acetyl cysteine is both an amine and a carboxylic acid. In addition, it contains the mercaptan or "sulfur alcohol" linkage (-SH). This mercaptan linkage enables disruption of sulfur-sulfur bond linkages in proteins found in mucus.
  
  

As a Mucolytic

• By breaking up di-sulfur bonds, N-acetyl cysteine shortens the chain-length of mucus proteins, thus thinning the mucus. Thus N-acetyl cysteine is useful in treating certain lung ailments that produce thickened mucus. These include bronchitis, pneumonia, cystic fibrosis and tuberculosis.
  
  

Treating Acetaminophen Poisoning

• N-acetyl cysteine is lifesaving when used intravenously in cases of acetaminophen poisoning. Acetaminophen, sometimes called Tylenol, is a safe and very useful medication taken when taken according to directions. However, acetaminophen is compounded into many other over-the-counter medications. If such medications in addition to a large dose of plain acetaminophen are taken, overdose may result. Metabolites produced during breakdown of the acetaminophen attack liver cells. N-acetyl cysteine stimulates the body's glutathione (GSH) production and the two substances, GSH and NAC, neutralize acetaminophen's metabolites. Administered in time, liver failure may be averted.
  
  

HIV/AIDS

• The University of Hawaii indicates NAC, as part of an antioxidant regimen, is a supplement used by persons afflicted with HIV/AIDS. It helps replenish glutathione levels. Curiously, another source indicates that if an excessive dose of NAC is taken, the opposite--oxidative stress--may actually increase.
  
  

Additional Benefits

• N-acetyl cysteine may, by boosting immune response, help prevent the development of influenza. NAC may boost the effectiveness of clomiphene--a drug taken to increase female fertility.
  
  

Advisories

• Be advised that use of N-acetyl cysteine weakens antibiotic effectiveness. When taken over a long period, NAC mineral depletion may call for zinc and copper supplementation in the diet. NAC may produce nausea, vomiting or diarrhea. NAC may raise levels of homocysteine, an amino acid believed to be associated with heart disease. If taking nitroglycerine, NAC may induce severe headaches and it can increase tolerance to nitroglycerine, making it less effective for angina sufferers.