Table 4.

Antioxidant treatments that have been tested in humans for treatment of coronavirus infections.

Mediators	Effect	References
Inhaled NO	↑ oxygenation in severe COVID-19, no effect on mortality	Lotz et al. (2021), Prakash et al. (2021)
Ubiquinol (CoQ10)	Does not ↓ the number or severity of PASC-related symptoms when compared to placebo	Hargreaves and Mantle (2021), Hansen et al. (2022)
N-acetyl cysteine	Oral high dose of N-acetyl cysteine may ↓ morbidity in severe COVID-19 in observational studies; many ongoing clinical trials with unpublished data	Wong et al. (2021), Izquierdo et al. (2022)
Glutathione	↓ reduces dyspnea in COVID-19 in a case series	Horowitz et al. (2020)
Melatonin	May improve clinical outcomes in patients with COVID-19 based on RCTs	Lan et al. (2022)
Vitamin C	Controversial data may have some benefit in morbidity in COVID-19 based on clinical trials	Olczak-Pruc et al. (2022)
Vitamins	Controversial data overall weak/negative; supplementation with vitamins A, B, C, D, and E could improve the inflammatory response and decrease the severity of disease in ICU-admitted patients with COVID-19	Beigmohammadi et al. (2021)
Zinc	Overall limited data/no major effect on morbidity in COVID-19, many ongoing clinical trials with unpublished data	Perera et al. (2020), Balboni et al. (2022)
Selenium	Overall limited data/no major effect on morbidity in COVID-19, many ongoing clinical trials with unpublished data	Alshammari et al. (2022), Balboni et al. (2022)
Pentoxifylline	May reduce lung inflammation, ongoing clinical trials with unpublished data	Feret et al. (2021)

Abbreviations: RCT, Randomized control clinical trial; PASC, Post Acute Sequalae of SARS-CoV-2 infection.