COVID-19: Is there evidence for the use of herbal medicines as adjuvant symptomatic therapy? - Silveira, D; Prieto-Garcia, J M; Boylan, F; Estrata, O; Fonseca-Bazzo, Y M; Jamal, C M; Magalhaes, P O; Pereira, E O; Tomczyk, M; Heinrich, M (Front Pharmacol, 2020)