While the clinical features of COVID-19 include pyrexia, asthenia, dyspnea, as well as acute respiratory distress syndrome, septic shock, and coagulation deficiencies in critically ill patients, there has been no standard pharmacotherapy to treat COVID-19. Vitamin A has potent physiological functions.

Some reports have suggested that vitamin A is necessary to maintain immune function and is responsible for immune cell differentiation and proliferation. It is also shown that vitamin A can improve the ability of immune cells to produce antibodies and activate T-lymphocytes to release functional lymphokines through modulation of target genes through nuclear receptors. It is also essential for maintaining sufficient levels of natural "killer cells" in circulating blood. Vitamin A adjuvant therapy may also improve the bodys immune function by increasing IgM and IgG levels and activating T lymphocytes. Vitamin A is also known to possess a significant role against pneumonia. 

It has been recommended that Vitamin A may serve as an optional treatment for COVID 19. Studies have shown that vitamin A may be clinically used to treat COVID 19 owing to its role as an anti-viral, anti-inflammatory, and immunomodulatory effect through different biological processes and cell signaling pathways. 

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