Objective:This study aims to investigate the mechanism of lansoprazole on skin inflammation through in vivo and in vitro experiments. Methods:In vivo experiment,mice were given continuous gavage for 6 months. The skin tissue damage of mice was evaluated and analyzed by hematoxylin-eosin staining(HE staining)and immunohistochemistry(IHC). In vitro experiment,CCK-8 was used to determine the changes of HaCaT cell viability after incubation with 10-200 μmol/L lansoprazole for 24 h and 48 h. After incubation with 10 μmol/L,20 μmol/L and 40 μmol/L lansoprazole for 24 h and 48 h,respectively,the phosphorylation levels of NF-κB in HaCaT cells and the protein expressions of interleukin(IL)-6 and IL-1β in HaCaT cells were detected by Western blot. In addition,the protein expressions of P-p65,IL-6 and IL-1β in HaCaT cells were detected after 24 h and 48 h incubation of HaCaT cells with pyrrolidine dithiocarbamate,an inhibitor of NF-κB signaling pathway,alone or in combination with lansoprazole. Results:In vivo experiment showed that lansoprazole can cause skin damage in mice. In vitro studies found that lansoprazole can decrease cell viability,increase the expression of P-p65 proteins,mediate the activation of the pathway,and further stimulate the expression of inflammatory cytokines IL-6 and IL-1β. PDTC can inhibit the lansoprazole-mediated activation of NF-κB pathway and reduce the expression of inflammatory factors. Conclusion:Lansoprazole can promote the expression of inflammatory factors and induce skin injury,and the mechanism may be related to the activation of NF-κB signaling pathway.