Herbal remedies and COVID-19: where is the evidence?
Seithikurippu R. Pandi-Perumal, Rajendra P. Maurya, Dinesh Chandra, Shalini Maurya, Om P. Singh, Rajneesh A. Tripathi, Yogesh C. Tripathi, Arup Giri, Vijay K. Bharti

The novel coronavirus disease 2019 (COVID-19) was widely regarded due to an unpredictable, imminent pandemic posing a significant threat to humanity. This new virus has high infectivity, mortality, and variable latency. The recurrent modification in the virus' genetic (antigenic) structures poses a challenge in successful vaccine development. While several vaccine trials are underway, many conventional drugs are repositioned (i.e. repurposing) and used for prophylactic and therapeutic purposes. However, the results were not very encouraging and often causing serious adverse effects. To come down the grimness and duration of acute disease and complexities, safe alternative remedies are, thus, needed. In symptomatic SARS-COV-2 patients, the traditional Chinese medicine (TMC) with allopathic drugs and Moroccan medicinal plant extract showed significant benefit. Traditional medicine derived from Indian herbal plants used since ancient times to treat human diseases in India is easily available and cost-effective without any side effects. Some compounds from Indian herbal plants such as phytonutrients, flavonoids, phytomelatonin, and others have been demonstrated to possess anti-inflammatory, immunomodulatory, and antiviral bioactivities. In this review, we discuss some of the potential herbal plants with antiviral properties based on the history of usefulness in either treating COVID-19 or other potential viral infections. Considering the benefits of these preparations, government agencies must take interest in these preventive therapies and allot more funding. More evidencebased, experimental (basic, translational, and clinical) studies are needed to establish its efficacy and safety of these ingredients either alone or in combination.

Keywords: Antioxidants, antiviral, COVID-19, herbal, immunoenhancement, plants, virus