ABSTRACT
Scientists are looking forward to a distinct therapeutic approach for treating coronavirus disease 2019 (COVID-19) worldwide. Existing treatments for COVID-19 can be repurposed and may reduce the pandemic's devastation. Over the past few years, studies on the immunomodulating effects of nutraceuticals against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have become trending prophylactic approaches. The potential use of medicinal herbs and their extracts is associated with understanding the most intriguing pathways that generate viral pathogenesis. These oral dietary supplements serve as the preventive and complementary therapeutic intervention for viral diseases including COVID-19 and other respiratory illnesses. Vitamin K deficiency is frequently observed in the early phases of COVID-19 infection and several studies hypothesize a peculiar link between vitamin K and COVID-19 clinical outcomes and related complications such as coagulopathy and thromboembolism. Because there has long been interest in the antiviral properties of nutraceuticals in this review, we critically appraise the nutraceutical importance of vitamin K as an antiviral supplement, from which it attributes its antiviral actions (either by direct action on viruses or by modulating the immune system) to its herbal sources. We also postulate the possible applications and potential benefits of using vitamin K against SARS-CoV-2 to improve disease outcomes.
