Cassia Cinnamon - Arava (Leflunomide) Interaction
Herbal: Cassia Cinnamon
Also Known As: Cinnamomum aromaticum, Bastard Cinnamon, Chinese Cinnamon, Ramulus Cinnamomi
Drug: Leflunomide
Brand names:
Arava
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
May 04, 2025
Interaction Details
Leflunomide is classified as belonging to the following category: Hepatotoxic Drugs
Theoretically, large doses of cassia cinnamon might cause additive effects when used with hepatotoxic drugs.
There is some concern that ingesting large amounts of cassia cinnamon for an extended duration might cause hepatotoxicity in some people. Cassia cinnamon contains coumarin, which can cause hepatotoxicity in animal models. In humans, very high doses of coumarin from 50-7000 mg/day can result in hepatotoxicity that resolves when coumarin use is discontinued. Lower amounts might also cause liver problems in sensitive people, such as those with liver disease or those taking potentially hepatotoxic agents.
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
- Press release. Cinnamon capsules to reduce blood sugar are medicinal products! Efficacy has not been scientifically proven - some products contain high levels of coumarin. Federal Institute of Risk Assessment (BfM), Germany, November 11, 2006. Available a
- Felter SP, Vassallo JD, Carlton BD, Daston GP. A safety assessment of coumarin taking into account species-specificity of toxicokinetics. Food Chem Toxicol 2006;44:462-75.
- Choi, J., Lee, K. T., Ka, H., Jung, W. T., Jung, H. J., and Park, H. J. Constituents of the essential oil of the Cinnamomum cassia stem bark and the biological properties. Arch Pharm Res 2001;24(5):418-423.
- Brancheau D, Patel B, Zughaib M. Do cinnamon supplements cause acute hepatitis? Am J Case Rep 2015;16:250-4.
Cassia Cinnamon Overview
Cassia cinnamon, also known as Chinese cinnamon or Cinnamomum cassia, is a type of cinnamon native to China and other parts of Southeast Asia. It is made from the bark of the Cinnamomum cassia tree, which is related to the Cinnamomum zeylanicum tree that is used to produce another type of cinnamon, Ceylon cinnamon.
Cassia cinnamon is typically darker in color and has a stronger, more pungent flavor than Ceylon cinnamon. It is less expensive and more widely available than Ceylon cinnamon, which makes it the most commonly used type of cinnamon in the world.
Cassia cinnamon has been used for medicinal purposes for centuries, and it is believed to have a number of health benefits. It is thought to have antioxidant and anti-inflammatory properties, and it is sometimes used to help regulate blood sugar levels and improve digestion.
Some cassia cinnamon products contain high levels of coumarin, which can be toxic to the liver if ingested in large amounts.
Leflunomide Overview
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Leflunomide is used alone or in combination with other medications to treat rheumatoid arthritis (a condition in which the body attacks its own joints, causing pain, swelling, and loss of function). Leflunomide is in a class of medications called disease-modifying antirheumatic drugs (DMARDs). It works by decreasing inflammation and slowing the progress of the condition, which can help improve the physical activity of people with rheumatoid arthritis.
Cassia Cinnamon - More Interactions
Cassia Cinnamon interacts with 414 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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