N-Acetyl Cysteine and Reduced Mortality Risk

Research synthesisModerate evidenceLarge effect4 studies · 3 beneficial · 1 neutral · 0 harmful

Across 4 studies, 3 reported beneficial effects of N-Acetyl Cysteine on reducing mortality risk, with effect sizes ranging from moderate to large. The most compelling evidence comes from meta-analyses in COVID-19 (41% risk reduction, RR=0.59) and rodenticide poisoning (OR=0.25-0.34), while one small clinical trial in infants found no significant effect. Study durations and doses were not consistently reported, precluding identification of a specific effective dose or treatment window.

Studied populations: patients with COVID-19, rodenticide poisoning, and non-acetaminophen induced acute liver injury

Caveats: Available evidence is overwhelmingly positive — clinical literature in this area is subject to publication bias (null-result studies are less likely to be published or indexed). Evidence base is small (only 4 studies) — conclusions should be considered preliminary. Doses and forms varied across studies; one null trial used nebulized NAC in infants with esophageal atresia, which may not generalize to other populations or routes of administration.

Generated May 13, 2026

Doses used in studies

Nac · mg/day: 800 (median 800, IQR 800–800) — 1 study

Safety in these studies

mechanical ventilationIncreased riskOR 3.88; CI, 1.14-13.29
the need for mechanical ventilation (OR 3.88; CI, 1.14-13.29) were significantly higher in the treatment group.
from: N-acetyl cysteine versus standard of care for non-acetaminophen induced acute liver injury
nausea and vomitingIncreased riskOR 3.99; CI, 1.42-11.19
the risk of developing nausea and vomiting (OR, 3.99; CI, 1.42-11.19) were significantly higher in the treatment group.
from: N-acetyl cysteine versus standard of care for non-acetaminophen induced acute liver injury
Overall tolerabilityReported
the majority of adverse events are transient and minor.
from: N-acetyl cysteine versus standard of care for non-acetaminophen induced acute liver injury
Overall tolerabilityReported
No specific adverse effects were observed in the study group.
from: Evaluation of nebulized N-acetyl cysteine in outcome of esophageal atresia with tracheoeso

4 of 4 papersPopulation:

COVID-19 clinical outcomes and N-acetylcysteine (CoViNAC study): a GRADE compliant meta-analysis of randomized controlled trials with molecular docking and dynamics simulation studies with Mpro of SARS-CoV-2.
- 2025-05-26
- Meta-Analysis · n = 1,125
- Cellular and molecular biology (Noisy-le-Grand, France) 71(5)
- - Seshadri Reddy Varikasuvu
  - Munikumar Manne
  - Subodh Kumar
  - Shiv Kumar Mudgal
  - Vikash Raj
  - Saurabh Varshney
  - Pratima Gupta
  - Ashoo Grover
  - Chanchal Goyal
  - Vanita Lal
  - Harminder Singh
  - Mona Lisa
  - Saransh Workshop Members
- PubMed: 40418545
- DOI: 10.14715/cmb/2025.71.5.13
2 Insights on
- Reduced Mortality Risk
- High evidence
NAC significantly reduced mortality (RR=0.59, 95% CI 0.39-0.88, p=0.01; I²=62%), indicating a 41% decreased risk of death.
Effect
Beneficial
Effect size
Large
Significant
Yes
N-Acetyl Cysteine in Rodenticide Poisoning: A Systematic Review and Meta-Analysis.
- 2022-11
- Meta-Analysis · n = 492
- Current reviews in clinical and experimental pharmacology 17(3)
- - Muhammed Rashid
  - Viji Pulikkel Chandran
  - Sreedharan Nair
  - Deepa Sudalai Muthu
  - Jemima Pappuraj
  - Krupa Ann Jacob
  - Balaji Sridhar
  - Karen Mark
  - Shabnam Hyder
  - Sohil Khan
  - Girish Thunga
- PubMed: 34455951
- DOI: 10.2174/2772432816666210825102726
4 Insights on
- Reduced Mortality Risk
- High evidence
Metaanalysis of RCTs (OR: 0.25; 95% CI: 0.11-0.59; n=2) and retrospective studies (OR: 0.34; 95% CI: 0.15-0.78; n=3) showed a significant reduction in mortality
Effect
Beneficial
Effect size
Large
Significant
Yes
N-acetyl cysteine versus standard of care for non-acetaminophen induced acute liver injury: a systematic review and meta-analysis.
- 2021-09
- Meta-Analysis · n = 11
- Annals of hepatology 24
- - Dhan Bahadur Shrestha
  - Pravash Budhathoki
  - Yub Raj Sedhai
  - Anurag Adhikari
  - Ayusha Poudel
  - Barun Aryal
  - Ramkaji Baniya
- PubMed: 33722689
- DOI: 10.1016/j.aohep.2021.100340
3 Insights on
- Reduced Mortality Risk
- High evidence
- Clinical
Use of NAC in non-acetaminophen induced ALI showed 53% reduction in mortality compared to standard of care (OR, 0.47; CI, 0.29-0.75)
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Evaluation of nebulized N-acetyl cysteine in outcome of esophageal atresia with tracheoesophegeal fistula.
- 2020-12
- Clinical Trial · n = 30
- Journal of pediatric surgery 55(12)
- - Gurmeet Singh
  - Anand Pandey
  - Gaurav Shandilya
  - Archika Gupta
  - J D Rawat
  - Ashish Wakhlu
  - S N Kureel
- PubMed: 32467034
- DOI: 10.1016/j.jpedsurg.2020.04.013
3 Insights on
- Reduced Mortality Risk
- High evidence
- Clinical
There was no significant (p = 0.41) difference in mortality between the groups.
Effect
Neutral
Effect size
Small
Significant
No
Dose
2 mL of 10% NAC, nebulized (2:5 dilution, every six hourly)

N-Acetyl Cysteine and Reduced Mortality Risk

COVID-19 clinical outcomes and N-acetylcysteine (CoViNAC study): a GRADE compliant meta-analysis of randomized controlled trials with molecular docking and dynamics simulation studies with Mpro of SARS-CoV-2.

N-Acetyl Cysteine in Rodenticide Poisoning: A Systematic Review and Meta-Analysis.

N-acetyl cysteine versus standard of care for non-acetaminophen induced acute liver injury: a systematic review and meta-analysis.

Evaluation of nebulized N-acetyl cysteine in outcome of esophageal atresia with tracheoesophegeal fistula.