There are multiple interactions reported between these two agents.

Interaction Details

Rivaroxaban is classified as belonging to the following category: P-Glycoprotein Substrates

It is unclear if kava inhibits P-glycoprotein (P-gp); research is conflicting.
In vitro research shows that kava can inhibit P-gp efflux. However, a clinical study in healthy volunteers shows that taking kava standardized to provide 225 mg kavalactones daily for 14 days does not affect the pharmacokinetics of digoxin, a P-gp substrate. It is possible that the use of other P-gp substrates or higher doses of kava might still inhibit P-gp.

Interaction Rating

Moderate

Likelihood of Occurrence

Possible

Interaction 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

  • Weiss J, Sauer A, Frank A, Unger M. Extracts and kavalactones of Piper methysticum G. Forst (kava-kava) inhibit P-glycoprotein in vitro. Drug Metab Dispos 2005;33:1580-3.
  • Gurley BJ, Swain A, Barone GW, et al. Effect of goldenseal (Hydrastis canadensis) and kava kava (Piper methysticum) supplementation on digoxin pharmacokinetics in humans. Drug Metab Dispos 2007;35:240-5.
  • Asher GN, Corbett AH, Hawke RL. Common Herbal Dietary Supplement-Drug Interactions. Am Fam Physician. 2017;96(2):101-107.

Interaction Details

Rivaroxaban is classified as belonging to the following category: Cytochrome P450 3A4 (Cyp3A4) Substrates

It is unclear if kava inhibits CYP3AA; research is conflicting.
Although in vitro research suggests that kava inhibits CYP3A4, more robust clinical evidence shows that kava has no effect on CYP3A4. In a clinical study in healthy volunteers, taking kava 1000 mg twice daily (containing a daily dose of 138 mg kavalactones) for 28 days had no effect on CYP3A4 activity.

Interaction Rating

Minor

Likelihood of Occurrence

Unlikely

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans.

References

  • Mathews JM, Etheridge AS, Black SR. Inhibition of human cytochrome P450 activities by kava extract and kavalactones. Drug Metab Dispos 2002;30:1153-7.
  • Unger M, Frank A. Simultaneous determination of the inhibitory potency of herbal extracts on the activity of six major cytochrome P450 enzymes using liquid chromatography/mass spectrometry and automated online extraction. Rapid Commun Mass Spectrom 2004;1
  • Gurley BJ, Gardner SF, Hubbard MA, et al. In vivo effects of goldenseal, kava kava, black cohosh, and valerian on human cytochrome P450 1A2, 2D6, 2E1, and 3A4/5 phenotypes. Clin Pharmacol Ther 2005;77:415-26.
  • Asher GN, Corbett AH, Hawke RL. Common Herbal Dietary Supplement-Drug Interactions. Am Fam Physician. 2017;96(2):101-107.

Kava Overview

Kava Kava is a tropical plant native to the Pacific Islands. The roots of the plant contain kavalactones, which are known to have sedative and relaxing effects. Kava has traditionally been used in social and cultural settings for its relaxant effects and is available as a dietary supplement to help with symptoms of anxiety and stress. It is important to note that Kava has been linked to causing liver damage and must be used cautiously, although the results of studies in this regard are mixed. Nevertheless, kava is banned in some parts of the world (e.g., the UK).
See More Information Regarding Kava

Rivaroxaban Overview

  • Rivaroxaban 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. Rivaroxaban is also used to prevent DVT and PE from happening again after initial treatment is completed in adults. It 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) that is not caused by heart valve disease. Rivaroxaban is also used to prevent DVT and PE in adults who are having hip replacement or knee replacement surgery or in people who are hospitalized for serious illnesses and are at risk of developing a clot due to decreased ability to move around or other risk factors. It is also used along with aspirin to lower the risk of a heart attack, stroke, or death in adults with coronary artery disease (narrowing of the blood vessels that supply blood to the heart) or peripheral arterial disease (poor circulation in the blood vessels that supply blood to the arms and legs). Rivaroxaban is also used to treat and prevent DVT and PE from happening again in children and certain infants who have received at least 5 days of initial anticoagulation (blood thinner) treatment. It is also used to prevent DVT and PE after heart surgery in children 2 years of age or older who have congenital heart disease (abnormality in the heart that develops before birth). Rivaroxaban is in a class of medications called factor Xa inhibitors. It works by blocking the action of a certain natural substance that helps blood clots to form.

See More Information Regarding Rivaroxaban

Kava - More Interactions

Kava interacts with 1126 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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Parts of this content are provided by the Therapeutic Research Center, LLC.

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.

© 2021 Therapeutic Research Center, LLC

Drug descriptions are provided by MedlinePlus.

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Dr. Brian Staiger, PharmD

In addition to being a clinical pharmacist specializing in pharmacotherapy, Dr. Brian Staiger is a registered herbalist through the American Herbalist Guild. He has combined his passion for pharmacy practice with the study of medical ethnobotany to improve patient care. Feel free to reach out about any of your herbal or medication questions!

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