{Reference Type}: Journal Article {Title}: Drug-drug interaction between danshensu and irbesartan and its potential mechanism. {Author}: Li Y;Liu L; {Journal}: Xenobiotica {Volume}: 54 {Issue}: 4 {Year}: 2024 Apr 14 {Factor}: 1.997 {DOI}: 10.1080/00498254.2024.2338183 {Abstract}: To uncover the effect of danshensu on irbesartan pharmacokinetics and its underlying mechanisms.To investigate the effect of danshensu on the pharmacokinetics of irbesartan, Sprague-Dawley rats (n = 6) were orally administered 30 mg/kg irbesartan alone (control group) or pre-treated with 160 mg/kg danshensu (experimental group). The effect of danshensu on the metabolic stability of irbesartan in RLMs was examined by LC-MS/MS method. The effect of danshensu on CYP2C9 activity was also determined.Danshensu markedly increased the AUC(0-t) (9573 ± 441 vs. 16157 ± 559 μg/L*h) and Cmax (821 ± 24 vs. 1231 ± 44 μg/L) of irbesartan. Danshensu prolonged the t1/2 (13.39 ± 0.98 vs. 16.04 ± 1.21 h) and decreased the clearance rate (2.27 ± 0.14 vs. 1.19 ± 0.10 L/h/kg) of irbesartan. Danshensu enhanced the metabolic stability of irbesartan in vitro with prolonged t1/2 (36.34 ± 11.68 vs. 48.62 ± 12.03 min) and reduced intrinsic clearance (38.14 ± 10.24 vs. 28.51 ± 9.06 μL/min/mg protein). Additionally, the IC50 value for CYP2C9 inhibition by danshensu was 35.74 μM.Danshensu enhanced systemic exposure of irbesartan by suppressing CYP2C9. The finding can also serve as a guidance for further investigation of danshensu-irbesartan interaction in clinical practice.