Multidrug treatment using Kampo medicine for COVID-19 and other viral infections

Multidrug treatment for COVID-19 and other viral infections

Abstract

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 and has since become a major global threat to human health. New drugs such as remdesivir, and molnupiravir were developed. They are effective to some extent, but expensive. Besides such chemical compounds, many natural compounds have been tested by researchers for COVID-19 treatment. Consequently, natural active compounds providing antiviral and/or anti-inflammatory effects, have been found. Kampo medicines (i.e., Kakkon-to, Sho-saiko-to-ka-kikyosekko, and Saiko-keishi-to), that are mainly created using organic plant-based ingredients, have been prescribed during the COVID-19 pandemic. Regarding treatment using Kampo medicines for COVID-19, a combination of Kakkon-to and Sho-saiko-to-ka-kikyo-sekko was reportedly effective for fever, suppressing disease progression in patients with COVID-19. Similarly, a combination of Saiko-keishi-to and minocycline that has also anti-SARS-CoV-2 and anti-inflammatory effects, was reportedly effective for COVID-19 in acute and subacute phases. Aforementioned multidrug treatment is more effective than single-drug treatment because of the synergistic effects associated with the different mechanisms of action of the concerned drugs. Patients with influenza are also treated using Kampo medicines such as a combination of Mao-to and Sho-saiko-to in consideration of their anti-influenza effects. Recently, multidrug treatments using Kampo medicines for monkey-pox, severe fever with thrombocytopenia syndrome, and Crimean-Congo hemorrhagic fever have been proposed. Taken together, multidrug treatments using Kampo medicines may be effective against a variety of viral infections. In any case, clinical trials are warranted to better assess the optimal doses and durations, as well as the efficacy and tolerability, before these multidrug treatments can be recommended on a wider basis.