Green Tea - Pradaxa (dabigatran) Interaction
Herbal: Green Tea
Also Known As: Camellia sinensis, Green Sencha Tea, Green Tea Extract, GTP, GTPF, Japanese Sencha Green Tea, Japanese Tea, Kunecatechins, Poly E, Polyphenon E, PTV, Té Verde, Tea Extract, Tea Green, Tea, Thé, Thé Vert, Yabukita, Yame Green Tea, Yame Tea
Drug: dabigatran
Brand names:
Pradaxa, Pradax

Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
Apr 13, 2025
Interaction Details
dabigatran is classified as belonging to the following category: P-Glycoprotein Substrates
Green tea might increase the levels and adverse effects of P-glycoprotein (P-gp) substrates.
In vitro research and case reports suggest that green tea inhibits drug efflux by P-gp, potentially increasing serum levels of P-gp substrates. Case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking green tea and certain P-gp substrates.
Interaction Rating
Likelihood of Occurrence
PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists
References
- Pochet S, Lechon AS, Lescrainier C, et al. Herb-anticancer drug interactions in real life based on VigiBase, the WHO global database. Sci Rep 2022;12(1):14178.
Interaction Details
dabigatran is classified as belonging to the following category: Anticoagulant/Antiplatelet Drugs
Theoretically, green tea may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Conflicting reports exist regarding the effect of green tea on bleeding risk when used with anticoagulant or antiplatelet drugs; however, most evidence suggests that drinking green tea in moderate amounts is unlikely to cause a significant interaction. Green tea contains small amounts of vitamin K, approximately 7 mcg per cup. Some case reports have associated the antagonism of warfarin with the vitamin K content of green tea. However, these reports are rare, and very large doses of green tea (about 8-16 cups daily) appear to be needed to cause these effects. Furthermore, the catechins and caffeine in green tea are reported to have antiplatelet activity.
Interaction Rating
Likelihood of Occurrence
UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
References
- Mitscher LA, Mitscher LA, Jung M, Shankel D, et al. Chemoprotection: a review of the potential therapeutic antioxidant properties of green tea (Camellia sinensis) and certain of its constituents. Med Res Rev 1997;17:327-65.
- Booth SL, Madabushi HT, Davidson KW, et al. Tea and coffee brews are not dietary sources of vitamin K-1 (phylloquinone). J Am Diet Assoc 1995;95:82-3.
- Lou FQ, Zhang MF, Zhang XG, et al. A study on tea-pigment in prevention of atherosclerosis. Chin Med J (Engl) 1989;102:579-83.
- Graham HN. Green tea composition, consumption, and polyphenol chemistry. Prev Med 1992;21:334-50.
- Taylor JR, Wilt VM. Probable antagonism of warfarin by green tea. Ann Pharmacother 1999;33:426-8.
- Heck AM, DeWitt BA, Lukes AL. Potential interactions between alternative therapies and warfarin. Am J Health Syst Pharm 2000;57:1221-7.
- Ali M, Afzal M. A potent inhibitor of thrombin stimulated platelet thromboxane formation from unprocessed tea. Prostaglandins Leukot Med 1987;27:9-13.
- Ardlie NG, Glew G, Schultz BG, Schwartz CJ. Inhibition and reversal of platelet aggregation by methyl xanthines. Thromb Diath Haemorrh 1967;18:670-3.
- Son DJ, Cho MR, Jin YR, et al. Antiplatelet effect of green tea catechins: a possible mechanism through arachidonic acid pathway. Prostaglandins Leukot Essent Fatty Acids 2004;71:25-31.
- Chan, H. T., So, L. T., Li, S. W., Siu, C. W., Lau, C. P., and Tse, H. F. Effect of herbal consumption on time in therapeutic range of warfarin therapy in patients with atrial fibrillation. J.Cardiovasc.Pharmacol. 2011;58(1):87-90.
- Nutescu EA, Shapiro NL, Ibrahim S, et al. Warfarin and its interactions with foods, herbs and other dietary supplements. Expert Opin Drug Saf. 2006;5(3):433-51.
Green Tea Overview

dabigatran Overview
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Dabigatran is used to treat deep vein thrombosis (DVT; a blood clot, usually in the leg) and pulmonary embolism (PE; a blood clot in the lung) in adults and children 3 months of age and older who have been treated with an injectable anticoagulant ('blood thinner'). It is also used to reduce the risk of a DVT and PE from happening again after initial treatment is completed in adults and children 3 months of age and older. Dabigatran is used to help prevent DVT and PE in adults who have had hip replacement surgery. Dabigatran is also used to help prevent strokes or serious blood clots in adults who have atrial fibrillation (a condition in which the heart beats irregularly, increasing the chance of clots forming in the body, and possibly causing strokes) without heart valve disease. Dabigatran is in a class of anticoagulant medications called direct thrombin inhibitors. It works by preventing blood clots from forming in the body.
Green Tea - More Interactions
Green Tea interacts with 1249 drugs
Interaction Rating Key
These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.
Major | The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur. |
Moderate | Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur. |
Minor | Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction. |
Unknown | No interactions have been reported or no interaction data is currently available. |
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
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Drug descriptions are provided by MedlinePlus.