Considerable evidence from both in vitro and animal studies suggests that CYP2D6 activity can be inhibited by goldenseal [59, 60], milk thistle [61, 62], kava kava [59, 63–65], Echinacea [59], and St. John’s wort [59, 66–68]. Currently, no in vitro results are available for black cohosh’s effect on CYP2D6, although certain triterpene glycosides isolated fromContinue reading “Safe herbs: milk thistle, kava kava, Echinacea, black cohosh and St. John’s wort”