The efficacy and mechanism of salmeterol against influenza A virus in vitro and in vivo

•Salmeterol was predicted to have activity against influenza A virus by using the network proximity analysis.•Salmeterol inhibited the activity of three IAV strains in the MDCK cells.•Salmeterol decreased the expression level of influenza A M2 and IFITM3 and inhibited the formation of NLRP3 inflammasome in infected mice.•Salmeterol increased the ratio of CD4+/CD8+ to regulate the imbalance of immune system in mice caused by viral infection.•Salmeterol protected A549 cells from cytopathic effect and reduced the production of inflammasome by decreasing the expression of RIG-1.