Is Arnica Cream Safe To Use If You Take Eliquis?
In our latest question and answer, our pharmacist discusses the safety of using arnica while taking the anticoagulant Eliquis (apixaban).
I use Eliquis and have sore back muscles. Is it safe to use arnica cream topical or does it interact with my blood thinner? Thanks.
Apr 25, 2023- Arnica has blood-thinning effects that could increase bleeding risk when combined with Eliquis, especially with oral forms or non-homeopathic topical preparations.
- Topical homeopathic arnica preparations are unlikely to cause significant interactions with Eliquis, though caution is still advised.
- You should talk to your doctor before using any arnica product while taking Eliquis to make sure it's safe for you.
Answer
Arnica is an herb that is often used in topical creams, ointments, and gels to relieve pain and inflammation associated with bruises, sprains, and sore muscles.
In regard to a potential drug interaction with anticoagulants like Eliquis, there is some concern as arnica has been reported to have blood-thinning effects.
However, it's important to note that the specific formulation of arnica is of importance here. An oral arnica supplement is most likely to have a clinically significant interaction, while topical arnica is less so (but is still possible depending on the formulation).
Homeopathic arnica preparations, which are very common, are unlikely to have significant interactions, but you should still be cautious with them.
Arnica Has Blood-Thinning Effects
Arnica contains compounds that can increase the risk of bleeding, especially when taken orally, or when used in large amounts topically (or if it is applied to broken skin).
The compounds in arnica responsible for its blood-thinning effects include sesquiterpene lactones and coumarins.
The sesquiterpene lactones in arnica have been shown to inhibit the activity of cyclooxygenase (COX) enzymes, which are involved in the production of inflammatory prostaglandins and blood platelet function.
Coumarins are compounds that have anticoagulant properties by inhibiting the activity of vitamin K-dependent coagulation factors. These factors are involved in the blood clotting process, so by inhibiting their activity, coumarins can reduce the blood's ability to clot.
In total, because arnica can interfere with the blood's ability to clot, it can be dangerous to use if you are already taking medications that affect blood clotting, like Eliquis.
Certain Arnica Formulations Are More Concerning Than Others
Arnica is available in many different forms and preparations.
The three most common are:
- Oral (in the form of tablets/liquid)
- Topical (creams, ointments)
- Homeopathic (both oral and topical)
If you are taking Eliquis, an anticoagulant, there is a definite concern with non-homeopathic oral and topical preparations (and even some concern with homeopathic ones).
It's worth noting that although it is often assumed that topical drugs don't share the same interaction risk that oral ones do, some arnica topical preparations can be absorbed into the bloodstream to an extent where a clinically significant interaction with Eliquis may occur.
This is more likely to happen with products that contain higher concentrations of arnica, longer duration of use, and larger areas of skin application. Several studies have noted some topical preparations can be significantly absorbed into the bloodstream (one such study can be found here).
With all of this being said, it's unlikely that topical homeopathic preparations of arnica would interact with Eliquis.
Homeopathy is based on the principle that "like cures like," meaning that a substance that causes symptoms in a healthy person can be used to treat similar symptoms in a sick person, and it involves the use of highly diluted substances to stimulate the body's natural healing processes. Many topical arnica preparations are homeopathic.
The concentration of arnica in homeopathic preparations is often low enough that it's unlikely to have a significant impact on blood clotting or interact with Eliquis.
Nevertheless, some topical homeopathic arnica preparations aren't highly diluted and still may pose a risk in some individuals, so caution is still advised with them.
Pharmacist Thoughts
You certainly want to avoid non-homeopathic oral arnica formulations if you are taking an anticoagulant like Eliquis.
Topical preparations would be safer to use, but since studies have shown that some can be significantly absorbed into the bloodstream, there is still a risk with them.
Additionally, while it's unlikely that a homeopathic preparation of arnica would pose a significant bleeding risk in those taking Eliquis, it is important to still be cautious as some may still contain an appreciable amount of the herb and pose a risk, depending on how absorbed it is.
As a general recommendation here, the optimal course of action would be to consult with your doctor before using any arnica preparation if you are taking anticoagulant medications like Eliquis.
Since your doctor has your complete medical history, they can advise you on the best course of treatment and recommend appropriate alternatives if necessary to avoid any potential interactions or adverse effects.
Final Words
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References & sources
- Helenalin, an anti-inflammatory sesquiterpene lactone from Arnica, selectively inhibits transcription factor NF-kappaB — PubMed
- Helenalin and 11 alpha,13-dihydrohelenalin, two constituents from Arnica montana L., inhibit human platelet function via thiol-dependent pathways — PubMed
- The effect of topical arnica on muscle pain — PubMed
- Skin penetration studies of Arnica preparations and of their sesquiterpene lactones — PubMed
- Permeation of bioactive constituents from Arnica montana preparations through human skin in-vitro — PubMed
Glossary — Terms in This Answer
- Anticoagulants
- Medications that reduce the blood's ability to clot and prevent dangerous blood clots from forming.
- Sesquiterpene lactones
- Chemical compounds found in arnica that can reduce inflammation and affect blood clotting.
- Coumarins
- Plant compounds with blood-thinning properties that block vitamin K-dependent factors needed for blood clotting.
- Cyclooxygenase (COX) enzymes
- Proteins in the body that produce inflammatory substances and are involved in blood platelet function.
- Vitamin K-dependent coagulation factors
- Proteins in the blood that require vitamin K to function and are essential for the blood clotting process.
- Homeopathic
- A system of medicine using highly diluted substances to stimulate the body's natural healing processes.
- Formulation
- The specific way a substance is prepared or combined, such as whether it is a tablet, cream, or diluted solution.
- Bioavailability
- The degree to which a substance is absorbed into the bloodstream and becomes available to affect the body.