Phytother Res. 2009 Mar;23(3):351-7. doi: 10.1002/ptr.2631.
Pharmacokinetic and pharmacodynamic study of interaction of Rhodiola rosea SHR-5 extract with warfarin and theophylline in rats.
Panossian A, Hovhannisyan A, Abrahamyan H, Gabrielyan E, Wikman G.
Swedish Herbal Institute Research and Development, Askloster, Sweden. alexander.panossian@shi.se

Abstract
Significant pharmacokinetic/pharmacodynamic interactions between various herbal products and drugs being substrates of cytochrome P450 have recently been reported. The aim of this study was to determine whether Rhodiola rosea SHR-5 extract interacts with warfarin and theophylline when administered concomitantly. Thus, concomitant treatment of rats with theophylline and SHR-5 did not give rise to significant effects on the pharmacokinetics of theophylline. Simultaneous administration of SHR-5 and warfarin did not alter significantly the pharmacokinetics or the anticoagulant activity of warfarin. It is concluded that SHR-5 might be of value in the treatment of patients with mild or moderate depression, and that its interaction with co-administered drugs is likely to be negligible.