HERBAL MEDICINES OR DIETARY SUPPLEMENTS AND WARFARIN AND OTHER ORAL ANTICOAGULANTS - GINSENG

One pharmacological study found that American ginseng (Panax quinquefolius) modestly decreased the effect of warfarin, whereas another study found that Panax ginseng did not alter the effect of warfarin. Two case reports describe decreased warfarin effects, one with thrombosis, attributed to the use of ginseng (probably Panax ginseng). Note that there have been reports of spontaneous bleeding with ginseng alone, and Panax ginseng has been found to contain antiplatelet components.
Until further information becomes available it would seem prudent to be alert for decreased effects of coumarins in patients using ginseng, particularly American ginseng. However, the possibility of an increased risk of bleeding due to the antiplatelet component of Panax ginseng cannot entirely be ruled out.