December 2020
Ba X. Hoang, Graeme Shaw, Willian Fang, and Bo Han
Abstract
Coronaviruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza viruses increase oxidative stress in the body leading to cellular and tissue damage. To combat this, administration of high-dose vitamin C (ascorbic acid or ascorbate), in addition to standard conventional supportive treatments, has been shown to be a safe and effective therapy for severe cases of respiratory viral infection.
Morbidity, mortality, infectiveness and spread of infectious diseases are dependent on the host–pathogen relationship. Given the lack of effective and safe antiviral drugs for coronaviruses, there should be more attention in supporting host immune defence, cytoprotection and immunoregulation. Implementation of high-dose vitamin C therapy could dramatically reduce the need for high doses of corticosteroids, antibacterials and antiviral drugs that may be immunosuppressive, adrenal depressive and toxic, complicating the disease course.
In order to effectively fight the novel SARS-CoV-2 virus, medical professionals should explore readily available pharmaceutical and nutritional therapeutic agents with proven antioxidant, anti-inflammatory and immunosupportive properties. Supplemental vitamin C may also provide additional benefits for the prevention of viral infections, shorten the disease course and lessen complications of the disease.
Conclusion
Viral infections such as SARS-CoV-2 (COVID-19), influenza, respiratory syncytial virus and many others are usually associated with increased oxidative stress leading to oxidative cellular and tissue damage resulting in multiorgan failure. Vitamin C has demonstrated favourable therapeutic properties and a good safety profile throughout a wide range of clinical applications. Administration of high-dose vitamin C as a therapeutic agent can favourably impact patients with viral pneumonia and ARDS in severe SARS-CoV-2 infection by decreasing inflammation and pathogen infectiveness and virulence, optimising immune defence, reducing tissue and organ injury, and improving the overall outcome of the disease.
Application of a high dose of vitamin C can dramatically reduce the need for treatment with high doses of corticosteroids, antibacterials and antiviral drugs. Vitamin C also can be effective for primary prevention of viral infections by boosting the innate immune response. In infected patients, vitamin C therapy may shorten the disease course and prevent complications of the disease [47], [79]. In addition to vitamin C, other nutraceutical antioxidants widely available as over-the-counter drugs or food supplements can be used to improve the redox balance and reduce tissue damage in patients with viral pneumonia and ARDS. These possible agents include, but are not limited to, tocopherol, lipoic acid, N-acetylcysteine, glutathione, l-carnitine, coenzyme-Q10, zinc and selenium compounds.
Given the fact that vitamin C is inexpensive and has a history of efficacy and safety in similar clinical circumstances, further investigation should be done on its prophylactic ability in low doses and therapeutic ability in high doses. Instead of traditional double-blind controlled clinical trials, we recommend conducting comprehensive retrospective studies comparing disease progression and post-infection complications among patients who were or were not self-administering vitamin C during the course of their disease. This may provide timely data on the possible preventive and therapeutic values of vitamin C for medical and public interest in the current COVID-19 pandemic.
