Dong Quai Interactions

Dong quai (Angelica sinensis) contains coumarin derivatives (ferulic acid, osthole) and has documented antiplatelet activity. A widely cited case report (Page & Lawrence, Pharmacotherapy 1999, PMID 10417036) described a woman whose INR rose to 4.9 within four weeks of adding dong quai 565 mg once to twice daily to stable warfarin.

Dong quai (Angelica sinensis) shows estrogen-agonist activity in vitro and promotes growth of estrogen receptor-positive breast cancer cells. Combining it with prescribed estrogen therapy may add unwanted estrogenic stimulation, and dong quai's coumarin content increases bleeding risk in patients also on hormone therapy with VTE risk.