AIM: To evaluate the anti-respiratory syncytial virus (RSV) effect of flavonoids extracted from the core of Litchi Chinensis in cell culture in vitro. METHODS: By the method of cell culture and using ribavirin as a positive control, the cytopathic effect(CPE) was observed. RESULTS: The TC50 and IC50 of the flavonoids extracted from the core of Litchi Chinensis was 152.9 mg/L and 58.6 mg/L respectively. The therapeutic index (TI) was 2.6, It had the same effect as Ribavirin in anti-RSV. Moreover, flavonoids ...