Intravenous vitamin C use and risk of severity and mortality in COVID-19: A systematic review and meta-analysis

Nutr Clin Pract. 2022 Apr;37(2):274-281. doi: 10.1002/ncp.10832. Epub 2022 Feb 11.


The administration of intravenous vitamin C (IV-VC) in treating patients with coronavirus disease 2019 (COVID-19) is still highly controversial. There have been no previous studies on the effect of IV-VC on the severity and mortality of COVID-19. Hence, we conducted a systematic review and meta-analysis to compare the disease severity and mortality in patients with COVID-19 who promptly received IV-VC treatment vs those who did not. We performed a comprehensive systematic search of seven health science databases, including PubMed, Embase, Cochrane Library, MEDLINE, Web of Science, China National Knowledge Infrastructure, and Wanfang Data, up to June 23, 2021. We identified a total of seven related articles, which were included in this study. This meta-analysis showed that IV-VC treatment did not affect disease severity compared with placebo treatment or usual care (odds ratio [OR], 0.70; 95% CI, 0.45 to 1.07; P = 0.10). In addition, no statistically significant difference in mortality was observed between patients who received IV-VC treatment and those who did not (OR, 0.64; 95% CI, 0.41 to 1.00; P = 0.05). Moreover, the adjusted meta-analysis revealed that the use of IV-VC did not influence disease severity (OR, 0.67; 95% CI, 0.34 to 1.31; P = 0.242) or mortality (OR, 1.02; 95% CI, 0.75 to 1.40; P = 0.877) in comparison with a control group. The results of this meta-analysis demonstrated that short-term IV-VC treatment did not reduce the risk of severity and mortality in patients with COVID-19.

Keywords: COVID-19; SARS-CoV-2; critical illness; disease severity; meta-analysis; mortality; vitamin C.

Publication types

  • Meta-Analysis
  • Review
  • Systematic Review

MeSH terms

  • Ascorbic Acid / therapeutic use
  • COVID-19 Drug Treatment*
  • China
  • Humans
  • SARS-CoV-2
  • Severity of Illness Index


  • Ascorbic Acid