Acetylcysteine - Research

Research

The following uses have not been well-established or investigated:

• Evidence that NAC and other antioxidants can exert beneficial effects on pancreatic b-cell function in diabetes was published in a 1999 study. The authors conclude that a sufficient supply of antioxidants (NAC, vitamin C plus vitamin E, or both) may prevent or delay b-cell dysfunction in diabetes by providing protection against glucose toxicity.

• NAC is undergoing clinical trials in the United States for the treatment of obsessive-compulsive disorder. It is thought to counteract the glutamate hyperactivity in OCD.
• NAC has had anecdotal reports and some research suggesting efficacy in preventing nail biting.
• NAC is being tested in a double blind trial in Systemic Lupus Erythematosus. The objective is to correct mitochondrial dysfunction.
• NAC has been shown to reduce cravings associated with chronic cocaine use in a study conducted at the Medical University of South Carolina.
• It may reduce the incidence of chronic obstructive pulmonary disease (COPD) exacerbations.
• In the treatment of AIDS, NAC has been shown to cause a "marked increase in immunological functions and plasma albumin concentrations". Albumin concentration are inversely correlated with muscle wasting (cachexia), a condition associated with AIDS.
• An animal study indicates that acetylcysteine may decrease mortality associated with influenza.
• Animal studies suggest that NAC may help prevent noise-induced hearing loss. A clinical trial to determine efficacy in preventing noise-induced sensorineural hearing loss in humans is currently (2006) being jointly conducted by the US Army and US Navy
• A human study of 262 primarily elderly individuals indicates that NAC may decrease influenza symptoms. In the study, 25% of virus-infected subjects who received NAC treatment developed symptoms whereas 79% in the placebo group developed symptoms.
• It has been suggested that NAC may help sufferers of Samter's triad by increasing levels of glutathione allowing faster breakdown of salicylates, though there is no evidence that it is of benefit.
• There are claims that acetylcysteine taken together with vitamin C and B₁ can be used to prevent and relieve symptoms of veisalgia (hangover following ethanol (alcohol) consumption). The claimed mechanism is through scavenging of acetaldehyde, a toxic intermediate in the metabolism of ethanol.
• It has been shown to help women with PCOS (polycystic ovary syndrome) to reduce insulin problems and possibly improve fertility.
• Small studies have shown acetylcysteine to be of benefit to sufferers of blepharitis.
• Studies in mouse models of Ataxia Telangiectasia (ATM knockout) indicate that NAC prevents genomic instability and retards lymphomagenesis in these animals. Clinical trials in human AT patients are underway.
• It has been shown to help trichotillomania, a condition causing compulsive hair-pulling as well as compulsive nailbiting.
• Sulfur and sulfur-related amino acids are commonly depleted in autism. Glutathione, which largely depends on cysteine for its formation, is also frequently depleted in autism, and may contribute to the heavy metal burden commonly found in autistic patients.
• Possible antidote for methylmercury poisoning. It produced an acceleration of urinary methyl-mercury excretion in mice.
• It has been shown effective in the treatment of Unverricht-Lundborg disease in an open trial in 4 patients. A marked decrease in myoclonus and some normalization of somatosensory evoked potentials with N-acetylcysteine treatment has been documented.
• Small reduction of cell death in chemotherapy patients, due to reduction in oxidative stress. Reduced ROS and lipid peroxidation, and restoration of antioxidant enzyme activities.
• Results of a research study published in the New England Journal of Medicine in November 2011, tested the effect of N-acetylcysteine in combination with glucocorticoids (combination group) for patients suffering from severe alcoholic hepatitis. The data showed that the combination of N-acetylcysteine with prednisolone decreased mortality significantly at one month compared to the prednisolone-only group (8% vs 24%, P=0.006). However, the improvement was not as significant at 3 months or 6 months (22% vs 34%, P=0.06) and (27% vs 38%, P=0.07). Factors that were associated with increased 6-month survival included younger age, shorter prothrombin time, lower levels of bilirubin in baseline studies, and decrease in bilirubin on day 14, all (P<0.001). Death due to hepatorenal syndrome occurred less frequently for the combination group at 6 months (9% vs 22%, P=0.02) and infections were also less frequent in the combination group as well (P=0.001). Six-month survival, the primary outcome, was not improved in conclusion.

• NAC appears to improve the clinical efficacy of B vitamins in patients with raised homocysteine and memory disorders, including dementia.