Dong Quai Interactions

Dong quai (Angelica sinensis) contains coumarin-family compounds (ferulic acid, osthole) and has antiplatelet activity in laboratory studies. A published case report described a previously stable warfarin patient whose INR climbed well above her target range within weeks of adding dong quai, then returned to normal after she stopped it. The signal rests on a single human case plus animal data, so it is taken seriously but is not extensively documented.

Dong quai (Angelica sinensis) shows estrogen-agonist activity in laboratory studies and can stimulate the growth of estrogen receptor-positive breast cancer cells in cell and animal models. Taken alongside prescribed estrogen, it adds an extra, unmeasured estrogenic signal in hormone-sensitive tissues. Dong quai also contains coumarin compounds that can add to bleeding risk, with one case report describing potentiation of warfarin.