Open Access Review

Determining the efficacy of N-acetyl cysteine in treatment of pneumonia in COVID-19 hospitalized patients: A meta-analysis

by Mohamed E.A Shaaban 1,*  and  Ahmed I.M Mohamed 1
Graduate of the Faculty of Pharmacy, Beni-Suef University, Beni-Suef, Egypt
Author to whom correspondence should be addressed.
IJCMR  2023, 6; 1(2), 6;
Received: 17 July 2023 / Accepted: 22 August 2023 / Published Online: 23 August 2023



Most patients infected with COVID-19 experienced cold-like symptoms. Some other patients developed more serious symptoms such as pneumonia. N-Acetylcysteine ​​(NAC) is known to be effective against acute respiratory distress syndrome (ARDS) due to its anti-inflammatory and antioxidant properties. The effect of NAC on hospitalized COVID-19 patients was unknown. Therefore, this meta-analysis aimed to establish a relationship between the effects of NAC and non-NAC protocols in inpatients with COVID-19.


By March 2022, a systemic review was conducted to assess the effects of NAC and non-NAC in inpatients with COVID-19. The clinical trials were identified in 20553 subjects admitted with COVID-19 at baseline. 2909 was treated with NAC and 17644 was treated without NAC. This study attempts to compare the effects of NAC and non-NAC in COVID-19 patients hospitalized with pneumonia. Statistical analysis uses the dichotomous method as a tool for odds ratio (OR) at  95% confidence interval (CI) to assess the effectiveness of NAC and non-NAC in COVID-19 patients hospitalized with pneumonia in random or fixed-effect model.


Patients managed with NAC had fewer days in the ICU (OR, 2.79; 95% CI, -1.11-6.69, = 0.16), lower mortality (OR, 0.69; 95% CI, 0.40-1.20, = 0.19), and fewer number needed mechanical ventilation (OR, 0.74; 95% CI, 0.25-2.21, = 0.59) compared with non-NAC in COVID-19 subjects hospitalized with pneumonia.


NAC has decreased the days stayed in the ICU, number of deaths, and number of patients needed mechanical ventilation in COVID-19 hospitalized with pneumonia, although, this difference was insignificant. Further studies are required that could affect the level of significance.

Copyright: © 2023 by E.A Shaaban and I.M Mohamed. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) (Creative Commons Attribution 4.0 International License). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

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ACS Style
E.A Shaaban, M.; I.M Mohamed, A. Determining the efficacy of N-acetyl cysteine in treatment of pneumonia in COVID-19 hospitalized patients: A meta-analysis. International Journal of Clinical Medical Research, 2023, 1, 6.
AMA Style
E.A Shaaban M, I.M Mohamed A. Determining the efficacy of N-acetyl cysteine in treatment of pneumonia in COVID-19 hospitalized patients: A meta-analysis. International Journal of Clinical Medical Research; 2023, 1(2):6.
Chicago/Turabian Style
E.A Shaaban, Mohamed; I.M Mohamed, Ahmed 2023. "Determining the efficacy of N-acetyl cysteine in treatment of pneumonia in COVID-19 hospitalized patients: A meta-analysis" International Journal of Clinical Medical Research 1, no.2:6.

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