Angelica may increase the risk of bleeding or potentiate the effects of warfarin therapy.

– Am J Health Syst Pharm 2000 Jul 1;57(13):1221-7; quiz 1228-30 —
Potential interactions between alternative therapies and warfarin. — Heck AM, DeWitt BA, Lukes AL. — School of Pharmacy and Pharmacal Sciences, Purdue University, Indianapolis, IN, USA.

We present a case of a man who developed gynaecomastia after ingestion of “Dong Quai” pills. “Dong Quai” is the Chinese name for the herb Angelica polymorpha var. sinensis which is widely used as a panacea for gynocological problems, and it is also proclaimed as an invigorating tonic for both women and men. The pharmacological effects of “Dong Quai” are likely related to the phytoestrogen that it contains. This report highlights the potential adverse effects associated with its consumption in the male, especially for the processed “Dong Quai” pills which may contain significantly higher levels of phytoestrogen than its original herbal product.
– Singapore Med J 2001 Mar;42(3):115-6 — Gynaecomastia and the herbal tonic “Dong Quai”. — Goh SY, Loh KC.