Observed herb/drug interactions associated with Dang Gui, Dong Quai, Tang-Kuei (Angelica sinensis). [Source]
| Patient Abstract |
Herb and Use |
Drug Believed to Interact |
Other Drugs Being Taken |
Medical Observation |
Mechanism |
Legitimacy |
| 46 year old woman with history of stroke, rheumatic heart disease and atrial fibrillation [44] |
Dong quai Angelica sinensis (Gynaecological conditions) |
Warfarin |
Digoxin, frusemide |
↑ INR |
Herb acts as Cox inhibitor |
Likely |
| Woman with history of mitral valve replacement [45] |
Dong quai Angelica sinensis (Gynaecological conditions) |
Warfarin |
None stated |
INR = 10, widespread bruising |
Herb acts as Cox inhibitor |
Possible |
Observed herb/drug interactions associated with Bing Lang and Da Fu Pi (Areca catechu). [Source]
| Patient Abstract |
Herb and Use |
Drug Believed to Interact |
Other Drugs Being Taken |
Medical Observation |
Mechanism |
Legitimacy |
| 51 year old man with schizophrenia [38] |
Betel nut Areca catechu (Stimulant) |
Fluphenazine |
Procyclidine |
Rigidity, bradykinesia, jaw tremor |
Not known |
Likely |
| 45 year old man with schizoaffective disorder |
Betel nut Areca catechu (Stimulant) |
Flupenthixol |
Procyclidine |
Stiffness, tremor, akathisia |
Not known |
Likely |
Observed herb/drug interactions associated with Dan Shen (Salvia miltiorrhiza). [Source]
| Patient Abstract |
Herb and Use |
Drug Believed to Interact |
Other Drugs Being Taken |
Medical Observation |
Mechanism |
Legitimacy |
| 66 year old man with atrial fibrillation, rheumatic mitral stenosis, cerebral embolism, and gastric adenocarcinoma [40] |
Danshen Salvia miltiorrhiza (Cardiovascular disease) |
Warfarin |
Digoxin, propranolol, topical oil containing 15% salicylates |
↑ INR; gastric bleeding but additive action due to coumarin content of herb |
Probably no interaction |
Possible |
| 62 year old man with mitral valve replacement [41] |
Danshen Salvia miltiorrhiza (Cardiovascular disease) |
Warfarin |
Digoxin, frusemide, captopril |
↑ INR but additive action due to coumarin content of herb |
Probably no interaction |
Likely |
| 48 year old woman with a history of rheumatic heart disease, mitral stenosis and atrial fibrillation [42] |
Danshen Salvia miltiorrhiza (Cardiovascular disease) |
Warfarin |
Digoxin frusemide, theophylline, mefenamic acid |
↑ INR but additive action due to coumarin content of herb |
Probably no interaction |
Possible |
Observed herb/drug interactions associated with ren shen Ginseng. [Source]
| Patient Abstract |
Herb and Use |
Drug Believed to Interact |
Other Drugs Being Taken |
Medical Observation |
Mechanism |
Legitimacy |
| 47 year old man with history of heart valve replacement [51] |
Ginseng Panax species (Fatigue) |
Warfarin |
Diltiazem nitroglycerin, salsalate |
INR decreased to 1.5 (previously stable 2–3) |
Herb has antiplatelet activity |
Likely |
| 42 year old woman with chronic depression [52] |
Ginseng Panax species (Fatigue) |
Phenelzine |
Lorazepam triazolam, bee pollen |
Manic symptoms |
Not known |
Possible |
| 64 year old woman [53] |
Ginseng Panax species (Fatigue) |
Phenelzine |
None |
Insomnia, headache, tremor |
Not known |
Unevaluable |

Ma Huang Ephedra, so misunderstood. :(
In December of 2000, CRN, or the Council for Responsible Nutrition (a dietary supplement trade group) provided the United States Food and Drug Administration (US FDA) a report demonstrating the safe upper limit dosage for ephedra, known as “ma huang” in Chinese medicine.
This industry group sought to determine the safe dosages for ephedra since there were reports coming in of adverse events such as high blood pressure and heart attacks following the ingestion of extremely large dosages of this herb for energy and weight loss. These uses were inconsistent with their uses in Chinese medicine. More… »

Chai Hu (Rx. Bupleurum) is a great herb for a variety of viral issues as well as stress-induced problems. Interferon therapy is designed to address viral issues as well. The interaction of Chai Hu (Rx. Bupleurum) and interferon is an additive problem. Interferon therapy boosts the strength and sensitivity of the immune system. Chai Hu (Rx. Bupleurum) has the same (but weaker) effect. When these two medicines are used together, they can give rise to an excessive immune response that damages the lungs. More… »
This is really more about a “side-effect” than an interaction.
Long-term high-dose use of gan cao (Licorice root) is associated with changes in how the kidneys excrete water. If you retain more water, it is possible for blood pressure to rise. Reports of this issue describe dosages of 273 to 546 mg per day [source], and 1,000 mg per day [source]. The typical dosage of gan can (Licorice root) used in Eagle herbs formulas varies between 10 – 20 mg per day. Not too much comparatively speaking. This is consistent with traditional uses of this herb. More… »