Medicinal plants have a mucoprotective effect, i.e. they are able to inhibit the entry of viruses and reduce RNA replication and virus titres. For specific recipes, even the production of antibodies has been noted.

Modern scientific studies have shown that some plants used in traditional oriental medicine have a proven antiviral effect against various viruses.

The article provides readers with an overview of some of these plants which in the focus of clinical studies on COVID-19 patients are considered as medicinal products with the potential to combat the onset of the disease, reduce symptoms and strengthen the body’s immune system.

These medicinal drugs act as a rich source of active substances which are referred to as “phytocomplex” and in particular the molecular complexity of these active substances is one of the strengths of the extracts gained from medicinal plants.

In the past ten years, several Asian medicinal plants have been analysed in view of their remarkable antiviral effects.

Glycyrrhiza uralensis Fisher (Gan Cao) roots for instance have been tested with regard to their efficacy against influenza A2 virus (H2N2), H5N1 virus, H1N1 virus and influenza A; hereby, a stimulation of the interferon gamma production has been observed as well as an immunomodulation with an anti-inflammatory effect and reduction of the virus infection in the host cells.

All mentioned studies prove that these medicinal plants are effective as prophlaxis and treatment of viral infections.