N-acetylcysteine (NAC) has a long history of use as a first-aid remedy for acetaminophen poisoning. Emergency room physicians will administer it in cases when you’ve taken an overdose of Tylenol or other acetaminophen products. The way it neutralizes the toxic effects of the drug is by recharging glutathione, thereby preventing liver damage.
Interestingly, NAC may also be useful against COVID-19, as explained by pulmonologist Dr. Roger Seheult in the MedCram lecture above. By raising glutathione, it helps combat oxidative stress, which is a main factor in the cytokine storm associated with COVID-19.
A recent literature analysis1 linked glutathione deficiency to COVID-19 disease severity, leading the author to conclude that NAC may be useful both for prevention and treatment. NAC may also combat the abnormal blood clotting seen in many cases, and helps loosen thick mucus in the lungs.
FDA Cracks Down on NAC
Interestingly, with COVID-19 treatment as a new indication, the U.S. Food and Drug Administration is now suddenly cracking down on NAC, claiming it is excluded from the definition of a dietary supplement, as it was approved as a new drug in 1985.2 As such, NAC cannot be marketed as a supplement.
You certainly would not suspect this looking at the supplement market. As reported by Natural Products Insider,3 there are no fewer than 1,170 NAC-containing products in the National Institutes of Health’s Dietary Supplement Label Database.
Be that as it may, July 29, 2020, FDA announced4 it has issued warning letters to seven companies that market NAC as a remedy for hangovers. According to the FDA:
“A hangover can occur after alcohol intoxication. Alcohol intoxication, like all poisonings, causes dose-related dysfunction and damage, ranging from mild impairments to death … The products outlined in these letters, which are labeled as dietary supplements, are unapproved new drugs and have not been evaluated by the FDA to be safe and effective for their intended use.”
Members of the Council for Responsible Nutrition have expressed concern that the warning letters may indicate the FDA is considering targeting NAC more widely.
