The loved and hunted amino acid derivative, N acetyl cysteine, offers a number of potential benefits to those seeking to recover from or prevent the occurrence of several diseases and conditions. Those of us practicing functional medicine love its multifaceted uses (as noted below). For some reason government regulators are hunting it and considering reclassifying it as a medication rather than a supplement. This combination has lead many people to both love and hunt it out on the shelves and online shopping carts to have a few bottles on hand in case the FDA does lock it down.
As with many other anti-oxidants, NAC’s uses vary widely due to its effects crossing over into nearly every body system. From its broad uses to thin mucous during respiratory illness and lower oxidative stress to its more focused uses in neuropsychiatric conditions or against cancer, NAC offers a very low side effect profile for the potential benefits it conveys. With rare severe effects and uncommon prevalence of milder effects, most can try it out without worrying about major problems. All the same, discussing implementation with a knowledgeable guide may help you avoid being one of those few who have problems with it.
Rather than producing an exhaustive list of NAC’s promising benefits, let’s focus on those we use in our office and those with the most potential benefit. The primary articles cited offer more details and references. For each area, a few starting references are also offered at the end of this article.
Detox: NAC acts in at least 2 ways to assist in detoxification of the human body. Directly, the sulfur sticking out from the amino acid backbone offers an active site to either bind unwanted heavy metals or offer a redox site to deal with free radicals and oxidative stress. Indirectly, the cysteine portion left over after the acetyl portion is removed augments the production of glutathione. This glutathione serves as a potent antioxidant helping to remove toxins through the kidneys or through direct toxin inactivation. The most widely accepted detox use would be for Tylenol overdose in which NAC helps reduce liver damage
Kidney disease: NAC has been extensively studied as a kidney protective agent especially in preventing damage by IV contrast during CT scans. For those with chronic kidney disease, the administration of NAC by IV prior to the IV contrast lowers the risk of harm to the kidneys. Many other studies have been done or are underway to look at other opportunities for kidney protection such as during surgery or for those who already have damaged kidneys.
Respiratory: NAC enjoys widespread use in upper and lower respiratory conditions where assistance with mucous clearance is important. From the common cold and sinus infections to chronic bronchitis and cystic fibrosis, NAC appears to offer symptomatic improvements by thinning mucous so that it can be coughed out.
Infections: Beyond the symptomatic improvements garnered from thinner mucous, NAC shows potential for some respiratory infections as well. Some studies on influenza indicated improvements in recovery and lessening of severity. In the past 2 years, several studies addressing COVID 19 have also indicated promising benefits for NAC in the treatment of this viral infection. Hopefully, the FDA will relent on its quest to make NAC a pharmaceutical and more research will confirm its benefits for COVID.
NAC’s activity as a biofilm disruptor may play a role in augmenting other anti-microbials. While the bacteria’s biofilm protects the underlying microbes, NAC’s ability to break up this protective blanket, allows other natural and pharma anti-microbials to penetrate and to kill the invaders.
Neuro-psychiatric: NAC offers potential in several neurologic and psychiatric conditions. The mechanisms are not perfectly understood, but the anti-oxidant properties appear to be the leading hypothesis. Past and present research suggests some benefits in Alzheimer’s disease and Parkinsons. NAC also shows promise in several psychiatric conditions including psychosis, anxiety, and bipolar.
As noted earlier, NAC demonstrates a very low risk of side effects. Like most therapies, GI disturbances are a possibility. If a patient has elevated metal toxins, NAC may initially worsen the related symptoms as toxin release occurs. While many ask if the sulfur in NAC could cross react with a Bactrim antibiotic allergy, the sulfur forms are different and should never be a contraindication. As with most therapies, you can get too much of a good thing. Excess sulfur in NAC or combined with other sulfur containing supplements may lead to excessive flatulence or nose bleeds.
Discuss with a knowledgeable provider regarding appropriate dose ranges for the condition you are wanting to support.
Šalamon, Špela et al. “Medical and Dietary Uses of N-Acetylcysteine.” Antioxidants (Basel, Switzerland) vol. 8,5 111. 28 Apr. 2019, doi:10.3390/antiox8050111
Mokhtari, Vida et al. “A Review on Various Uses of N-Acetyl Cysteine.” Cell journal vol. 19,1 (2017): 11-17. doi:10.22074/cellj.2016.4872
Zhang, Ding et al. “Protective effects of zinc and N-acetyl-L-cysteine supplementation against cadmium induced erythrocyte cytotoxicity in Arbor Acres broiler chickens (Gallus gallus domesticus).” Ecotoxicology and environmental safety vol. 163 (2018): 331-339. doi:10.1016/j.ecoenv.2018.07.069
Flora, Swaran J S. “Structural, chemical and biological aspects of antioxidants for strategies against metal and metalloid exposure.” Oxidative medicine and cellular longevity vol. 2,4 (2009): 191-206. doi:10.4161/oxim.2.4.9112
Duong, Michael H et al. “N-acetylcysteine prophylaxis significantly reduces the risk of radiocontrast-induced nephropathy: comprehensive meta-analysis.” Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions vol. 64,4 (2005): 471-9. doi:10.1002/ccd.20342
Ye, Minyuan et al. “N-acetylcysteine for chronic kidney disease: a systematic review and meta-analysis.” American journal of translational research vol. 13,4 2472-2485. 15 Apr. 2021
Grandjean, E M et al. “Efficacy of oral long-term N-acetylcysteine in chronic bronchopulmonary disease: a meta-analysis of published double-blind, placebo-controlled clinical trials.” Clinical therapeutics vol. 22,2 (2000): 209-21. doi:10.1016/S0149-2918(00)88479-9
De Flora, S et al. “Attenuation of influenza-like symptomatology and improvement of cell-mediated immunity with long-term N-acetylcysteine treatment.” The European respiratory journal vol. 10,7 (1997): 1535-41. doi:10.1183/09031936.97.10071535
De Flora, Silvio et al. “Rationale for the use of N-acetylcysteine in both prevention and adjuvant therapy of COVID-19.” FASEB journal : official publication of the Federation of American Societies for Experimental Biology vol. 34,10 (2020): 13185-13193. doi:10.1096/fj.202001807
Ibrahim, Homam et al. “Therapeutic blockade of inflammation in severe COVID-19 infection with intravenous N-acetylcysteine.” Clinical immunology (Orlando, Fla.) vol. 219 (2020): 108544. doi:10.1016/j.clim.2020.108544
Moreira, Paula I et al. “Lipoic acid and N-acetyl cysteine decrease mitochondrial-related oxidative stress in Alzheimer disease patient fibroblasts.” Journal of Alzheimer’s disease : JAD vol. 12,2 (2007): 195-206. doi:10.3233/jad-2007-12210
Parachikova, Anna et al. “Formulation of a medical food cocktail for Alzheimer’s disease: beneficial effects on cognition and neuropathology in a mouse model of the disease.” PloS one vol. 5,11 e14015. 17 Nov. 2010, doi:10.1371/journal.pone.0014015
Rapado-Castro, M et al. “Cognitive effects of adjunctive N-acetyl cysteine in psychosis.” Psychological medicine vol. 47,5 (2017): 866-876. doi:10.1017/S0033291716002932
Deepmala et al. “Clinical trials of N-acetylcysteine in psychiatry and neurology: A systematic review.” Neuroscience and biobehavioral reviews vol. 55 (2015): 294-321. doi:10.1016/j.neubiorev.2015.04.015
This article offers educational insight on the uses of a supplement to optimize health. It does not constitute medical advice for any individual. Any decision to implement the use of a supplement rests solely on the reader and his or her medical provider rather than Sanctuary Functional Medicine or its staff unless we are your provider. For our patients, discuss this supplement before implementing. For those who are not our patients, consult your provider before implementing.
Sanctuary Functional Medicine, under the direction of Dr Eric Potter, IFMCP MD, provides functional medicine services to Nashville, Middle Tennessee and beyond. We frequently treat patients from Kentucky, Alabama, Mississippi, Georgia, Ohio, Indiana, and more... offering the hope of healthier more abundant lives to those with chronic illness.