High-dose IV vitamin C treatment is an intervention under investigation to support patients infected with COVID-19.

Previous research has linked high dose Vitamin C to decreased death in patients with infections and more research is needed on this promising treatment.  A  2017 study found that high-dose IV vitamin C treatment (along with thiamine and corticosteroids) linked to decreased deaths among people with sepsis, a form of overwhelming infection-causing dangerously low blood pressure and organ failure.  A study published in 2019 also investigated the effect of high-dose vitamin C infusions in patients with severe infections who had sepsis and acute respiratory distress syndrome (ARDS). This study found a lower death rate. Though neither of these studies looked at vitamin C use in patients with COVID-19, the vitamin therapy was specifically given for sepsis and ARDS, and these are the most common conditions leading to intensive care unit admission, ventilator support, or death among those with severe COVID-19 infections. (Source: Harvard Health)

Here is information on clinical trials using Vitamin C for COVID-19

Vitamin C Infusion for the Treatment of Severe 2019-nCoV Infected Pneumonia

Study description: 2019 new coronavirus (2019-nCoV) infected pneumonia, namely severe acute respiratory infection (SARI) has caused global concern and emergency. There is a lack of effective targeted antiviral drugs, and symptomatic supportive treatment is still the current main treatment for SARI.

Vitamin C is significant to human body and plays a role in reducing inflammatory response and preventing common cold. In addtion, a few studies have shown that vitamin C deficiency is related to the increased risk and severity of influenza infections.

We hypothize that Vitamin C infusion can help improve the prognosis of patients with SARI. Therefore, it is necessary to study the clinical efficacy and safety of vitamin C for the clinical management of SARI through randomized controlled trials during the current epidemic of SARI.

Responsible Party:ZhiYong Peng, Professor; Chief physician, Zhongnan Hospital
ClinicalTrials.gov Identifier:NCT04264533

Published research to know.

The effectiveness of vitamin C in preventing and relieving the symptoms of virus-induced respiratory infections.

J Manipulative Physiol Ther. 1999 Oct;22(8):530-3.

METHOD: Investigators tracked the number of reports of cold and flu symptoms among the 1991 test population of the facility compared with the reports of like symptoms among the 1990 control population. Those in the control population reporting symptoms were treated with pain relievers and decongestants, whereas those in the test population reporting symptoms were treated with hourly doses of 1000 mg of Vitamin C for the first 6 hours and then 3 times daily thereafter. Those not reporting symptoms in the test group were also administered 1000-mg doses 3 times daily.

RESULTS: Overall, reported flu and cold symptoms in the test group decreased 85% compared with the control group after the administration of megadose Vitamin C.

CONCLUSION: Vitamin C in megadoses administered before or after the appearance of cold and flu symptoms relieved and prevented the symptoms in the test population compared with the control group.

Potential interventions for novel coronavirus in China: A systematic review

2.1.3 Vitamin C

Vitamin C is another water‐soluble vitamin and it is also called ascorbic acid, which means “no‐scurvy acid.” Vitamin C is best known for its role in the synthesis of collagen in connective tissues and acts as an antioxidant. Vitamin C also supports immune functions and protects against infection caused by a coronavirus.21 For example, Atherton et al22 had reported that vitamin C increased the resistance of chick embryo tracheal organ cultures to avian coronavirus infection. Vitamin C may also function as a weak antihistamine agent to provide relief from flu‐like symptoms such as sneezing, a running or stuffy nose, and swollen sinuses.23 Three human controlled trials had reported that there was significantly lower incidence of pneumonia in vitamin C‐supplemented groups, suggesting that vitamin C might prevent the susceptibility to lower respiratory tract infections under certain conditions.24 The COVID‐19 had been reported to cause lower respiratory tract infection, so vitamin C could be one of the effective choices for the treatment of COVID‐19.

Zhang, LLiu, YPotential interventions for novel coronavirus in China: A systematic reviewJ Med Virol202092479– 490https://doi.org/10.1002/jmv.25707

A New Mechanism of Vitamin C Effects on A/FM/1/47(H1N1) Virus-Induced Pneumonia in Restraint-Stressed Mice


It is well known that vitamin C could protect against influenza infection, but little is known about the mechanisms. This study aimed to investigate the influence and possible mechanisms of vitamin C on pneumonia induced by influenza virus in stressed mice. Results showed that restraint stress significantly increased the mortality and the severity of pneumonia in mice caused by A/FM/1/47(H1N1) virus infection, which was attenuated by oral administration of vitamin C (125 and 250 mg/kg). Moreover, vitamin C administration significantly decreased expression of susceptibility genes, including mitochondrial antiviral signaling (MAVS) and interferon regulatory factor 3 (IRF3), and increased expression of NF-κB. These work in conjunction to induce type I interferons (IFNs) and elicit innate antiviral response as key factors in RIG-I-mediated signal transduction pathway. The above effects of vitamin C were further found to relate with inhibition of excess CORT synthesis by regulating steroid hydroxylating enzymes in adrenal gland. In conclusion, the protective effects of vitamin C on influenza virus-caused pneumonia might be related to its inhibition of CORT synthesis, which reduces the susceptibility to influenza viral infection in restraint-stressed mice. These findings provide a new mechanism for the effects of vitamin C on influenza virus-induced pneumonia in restraint-stressed mice.

Cai Y, Li YF, Tang LP, et al. A new mechanism of vitamin C effects on A/FM/1/47(H1N1) virus-induced pneumonia in restraint-stressed mice. Biomed Res Int. 2015;2015:675149. doi:10.1155/2015/675149 

Can early and high intravenous dose of vitamin C prevent and treat coronavirus disease 2019 (COVID-19)?

The COVID-19 (SARS-2-Cov) pandemic, first reported in Wuhan, China, is now spreading to many continents and countries, causing a severe public health burden. Currently, there is no vaccine or specific antiviral drug for this deadly disease. A quick, deployable and accessible, effective and safe treatment is urgently needed to save lives and curtail the spreading. Acute respiratory distress syndrome (ARDS) is a key factor of fatality. Significantly increased oxidative stress due to rapid release of free radicals and cytokines is the hallmark of ARDS which leads to cellular injury, organ failure and death. Early use of large dose antioxidants, such as vitamin C (VC) may become an effective treatment for these patients. Clinical studies also show that high-dose oral VC provides certain protection against viral infection. Neither intravenous nor oral administration of high-dose VC is associated with significant side effects. Therefore, this regimen should be included in the treatment of COVID-19 and used as a preventative measure for susceptible populations such as healthcare workers with higher exposure risks.

Cheng, R. Z. (2020). Can early and high intravenous dose of vitamin C prevent and treat coronavirus disease 2019 (COVID-19)? Medicine in Drug Discovery, 100028. https://doi.org/10.1016/J.MEDIDD.2020.100028