Possible Interaction: St John's Wort and Imatinib

“ Hypericum extract , by inducing both the CYP3A4 and the P-glycoprotein (P-gp), can reduce the plasma concentrations of different antineoplastic agents such as imatinib , irinotecan and docetaxel, thus reducing the clinical efficacy of these drugs.”

“In healthy subjects, treatment with St John's wort for 2 weeks significantly decreased the systemic exposure of imatinib by 32%.”

“In healthy subjects, 2 weeks of treatment with St John's wort at 900 mg/day significantly decreased the systemic exposure of imatinib by 32%.”

“Well-documented SJW interactions include (1) reduced blood cyclosporin concentration, as suggested by multiple case reports as well as … when SJW was given with serotonin reuptake inhibitors, (3) unwanted pregnancies in women while using oral contraceptives and SJW , and (4) reduced plasma drug …) and anticancer (i.e., irinotecan, imatinib) ….”

“Clinical trials indicate …’s wort Hypericum perforatum ), via cytochrome P450 (CYP) and/or P-glycoprotein induction, reduces the plasma concentrations (… the clearance) of alprazolam, amitriptyline, atorvastatin, chlorzoxazone, ciclosporin, debrisoquine, digoxin, erythromycin, fexofenadine, gliclazide, imatinib , indinavir, irinotecan, ivabradine, mephenytoin, methadone, midazolam, nifedipine, omeprazole, …, simvastatin, tacrolimus, talinolol, verapamil, voriconazole and warfarin.”

“Such a relevant interaction is that of St. John's wort with the anticancer drugs irinotecan and imatinib.”