A narrative review of herbal preparations against RNA viruses

Objective Although several therapeutics were designed to control infectious diseases, viral infections are still fatal. Currently, evidence extracted from in vivo, in vitro and in silica studies support the antiviral activity of many herbs scientifically;however, the therapeutic potential of many other herbs is still unknown. Plants and their products may potentially control the propagation of viruses in a variety of conditions. Methods Data were extracted from PubMed, Scopus, Google Scholar, and Science Direct from 1983 to 2020. We gathered a list of plant extracts, phytochemicals, and herbal formulations that can inhibit RNA viral infections, mainly those are originated from the coronaviruses family. We also provided an overview of their inhibitory mechanism of actions. Results Plant families, including Lamiaceae, Asteraceae, and Myrtaceae, contain the highest number of species with anti-coronaviruses activities, respectively. Conclusions It can be suggested that the combination of these antiviral ingredients with each other, any synthetic compound, or already approved drugs or inhibitors can be a novel approach for antiviral therapies.