Abstract:Objective: Our study aims to evaluate the antiviral effects of Ouyi antipyretic detoxicate soft capsule against influenza A virus H1N1 in vivo, so as to find an effective Chinese medicinal formulae for the treatment of the virus infection, which may lay a theoretical foundation for clinic treatment of patient infected with Influenza A Virus H1N1. Method: With the observation of cytopathic effect (CPE) that induced by virus, we investigated viral inhibition rate by MTT colorimetric assay and valued antiviral activity of drugs by therapeutic index (TI). Meanwhile, Oseltamivir phosphate capsule(Tamiflu) was used as positive control, we carried out experiments through the three ways of preventive effect, direct inactivation and propagation inhibition. Result: Ouyiantipyretic detoxicate soft capsule could effectively inhibit cytopathic effect (CPE) that induced by Influenza A Virus H1N1. The preventive effect, direct inactivation, and inhibition of endogenous multiplication of Ouyi antipyretic detoxicate soft capsule and Tamiflu against influenza A virus H1N1 were observed. And three types of action therapeutic index(TI) from Ouyi antipyretic detoxicate soft capsule were (15.5±0.71), (0.55±0.071), (6.4±1.27) severally, comparing Tamiflu with (0.4±0.14), (1.88±0.29), (4.6±0.15), respectively. Conclusion: Ouyiantipyretic detoxicate soft capsule showed more remarkable preventive effect than Tamiflu in vitro(P<0.01). The possible mechanism of the antiviral activity observed in our study might be the protection of the MDCK cells from viral infection by inhibiting the viral absorption. We need a further study to certify three effects in vivo.