BACKGROUND: Tofacitinib is an orally administered Janus kinase (JAK) inhibitor that has demonstrated significant efficacy in the treatment of rheumatoid arthritis. This study aimed to investigate the effects of gliquidone and linagliptin, two hypoglycemic agents on the pharmacokinetics of tofacitinib in vitro and in vivo. METHODS: The mechanism of drug-drug interaction was studied in vitro using a murine liver microsome incubation system and in vivo by administering gliquidone and linagliptin orally to rats pretreated with various concentrations of tofacitinib. This study used waters ACQUITY UPLC I-Class/Xevo TQD ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometer. Furthermore, molecular docking was performed to simulate the interaction using computer simulations. RESULTS: Gliquidone and linagliptin inhibited the metabolism of tofacitinib by heparanase in vitro with IC CONCLUSION: Gliquidone and linagliptin significantly altered the pharmacokinetics of tofacitinib in vitro and in vivo. This study demonstrated the drug-drug interactions between linagliptin, gliquidone, and tofacitinib, highlighting the need for clinical attention to this possibility.