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Dietary supplement

Arnica Ingredients & Drug Interactions

by Herb Pharm

Arnica label
See full label image
Liquid Category: Botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 23, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Arnica against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Arnica is a dietary supplement by Herb Pharm with 1 active ingredient. Its ingredients are commonly taken for bruising, muscle soreness, joint pain (osteoarthritis).Based on those ingredients, 122 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Arnica liquid extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Arnica by Herb Pharm

Ask about any prescription or over-the-counter medication and we check it for interactions with Arnica by Herb Pharm — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Arnica by Herb Pharm

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 16, 2026

What’s inside

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 0 of its 1 active ingredient.

This product contains one active ingredient: arnica liquid extract, made from arnica flowers. The extract also includes certified organic alcohol and distilled water as part of the formulation.

Arnica has a long history in herbal medicine, especially for musculoskeletal complaints and inflammation.

Does it work?

Moderate evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: bruising and minor muscle soreness relief.
  • We looked for evidence on: Bruises, Exercise-induced muscle soreness, Postoperative swelling, Postoperative pain, Osteoarthritis, sprains — and 1 related terms.
  • The strongest evidence on file: Arnica is rated "Possibly Effective" for Osteoarthritis (Natural Medicines).
  • Also on file: Arnica is rated "Insufficient Reliable Evidence To Rate" for Exercise-induced muscle soreness, Postoperative pain, Bruises, Postoperative swelling.

The evidence is clearest for osteoarthritis, where arnica is rated possibly effective—meaning there's some supporting evidence, but it's not definitive. For acne, breast cancer-related hot flashes, postoperative pain, and dry eye, the reliable evidence isn't there yet to say whether arnica helps.

We simply don't have enough solid data to rate it one way or the other for those uses.

The evidence, ingredient by ingredient Arnica

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Here's the critical point: undiluted arnica taken by mouth is unsafe and can cause serious toxicity, including bleeding, stomach upset, muscle paralysis, and in rare cases, dangerous heart rhythms, coma, or organ failure. When used in very dilute homeopathic doses, arnica is generally well tolerated.

Topical arnica (applied to skin) also appears generally well tolerated, though contact dermatitis and skin irritation can occur. The safety data for pregnancy and breastfeeding is insufficient, and the current guidance is to avoid it during both.

If you're pregnant, planning to become pregnant, or breastfeeding, talk with your doctor or pharmacist about whether this product is right for you.

Side effects, ingredient by ingredient Arnica

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Arnica.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs.
  • For scale: 122 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, confirm with your doctor or pharmacist whether you're on any blood thinners or antiplatelet medications (like warfarin, clopidogrel, or aspirin). The arnica extract may increase your bleeding risk when combined with these drugs.

No other medication interactions are documented in our data, but that doesn't mean none exist—always run your complete medication list through the checker on this page or ask your pharmacist.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

This arnica extract may help with osteoarthritis, but the evidence for other uses is still unclear. The biggest caution is if you take blood thinners or antiplatelet drugs—check with your doctor or pharmacist first.

Pregnant or breastfeeding? The safety data isn't there, so it's best to discuss it with your healthcare provider before using.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Nov 25, 2014.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Arnica, straight from the product label.

Brand Herb Pharm
Barcode (UPC) 090700001032
Net contents 4 fl. Oz.; 118.4 mL
Market status On market
Date entered into DSLD Nov 25, 2014
DSLD ID 39412
Product type Botanical
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Arnica by Herb Pharm, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
10 Drop(s)
Maximum serving Sizes:
10 Drop(s)
UPC/BARCODE
090700001032
IngredientAmount% DV
Arnica liquid extract0 NP--

Other ingredients: certified organic Alcohol, distilled Water, Arnica extractives

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Suggested/Recommended/Usage/Directions

SUGGESTED USE Shake Well Before Using Internal: Take up to 10 drops in 8 oz. of water or juice, 1 to 3 times per day. Best taken between meals. Topical: One to three times per day gently rub a small amount into the affected area until well absorbed.

Precautions

Caution: Do not use during pregnancy, if trying to become pregnant or while nursing.

Not for use in excited nervous states, gastrointestinal irritation, acute inflammation or high fever.

Consult expert medical advice before using in children under 15 years of age, asthma, the aged and severely weakend individuals.

Do not exceed recommended dose and limit internal use to two consecutive weeks followed by a two week break. Do not use on broken or abraded skin. Discontinue use if irritation appears on skin or in mouth, throat or stomach. Prolonged topical use or use on broken skin may cause skin irritation

Keep Out of the Reach of Children

Storage

Store away from heat & light

General

011

General Statements

NERVOUS SYSTEM Minor Pain

We prepare our Arnica Extract from the whole flowers of Arnica montana plants which are Certified Organically Grown and/or Sustainably Wildcrafted in their native, high mountain habitat.

To assure optimal extraction of Arnica's bioactive compounds, the plants are hand-harvested when in full flower, are carefully shade-dried to retain their full color and aroma, and are then thoroughly extracted.

FDA Statement of Identity

HERBAL SUPPLEMENT

Formulation

GLUTEN-FREE

FDA Disclaimer Statement

THESE STATEMENTS HAVE NOT BEEN EVALUATED BY THE FDA. THIS PRODUCT IS NOT INTENDED TO DIAGNOSE, TREAT, CURE OR PREVENT ANY DISEASE.

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Arnica by Herb Pharm label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Arnica label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Arnica by Herb Pharm

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size10 Drop(s) Dosage formLiquid Amounts shown are per serving.

Arnica liquid extract

Interacts with
122 drugs
0 NP per serving

Arnica is a daisy-family plant used mainly in topical and homeopathic products for bruising, muscle soreness, and pain. The evidence is mixed and most...

Arnica liquid extract monograph & interactions

Other (inactive) ingredients: Certified organic Alcohol, Distilled Water, Arnica extractives. These complete the product’s ingredient list but are not active constituents.

Interaction report

Arnica by Herb Pharm Drug Interactions

Want to check YOUR meds against Arnica?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
122Drugs
122 Moderate

Ingredients driving the most interactions

Arnica liquid extract 122

Individual Drug Interactions

The ingredients in Arnica interact with 122 drugs. Click any drug to see the details.

1 of the 1 ingredient in Arnica interact with drugs. Each result below shows which ingredient is responsible. Arnica liquid extract

Each ingredient & the kinds of drugs it affects

For each ingredient in Arnica with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Arnica liquid extract1 drug type · 122 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, arnica might have additive effects with anticoagulant and antiplatelet drugs. Homeopathic arnica preparations are unlikely to have this interaction.
In vitro evidence shows that sesquiterpene lactones in arnica flowers can decrease platelet aggregation. However, this effect has not been reported in humans.

Likelihood Unlikely Evidence D
Arnica liquid extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Arnica, from the product label.

Herb Pharm

See all Herb Pharm products
Name
Herb Pharm
City
Williams
State
OR
ZipCode
97544
Phone Number
800-348-4372
Web Address
www.herb-pharm.com
Pharmacist Counseling Corner

Arnica by Herb Pharm: Common Questions

Does Arnica by Herb Pharm interact with any medications?
Yes. Based on its ingredients, Arnica has a known interaction with 122 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Arnica contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is it safe to take arnica liquid extract by mouth?
No. Undiluted arnica taken by mouth is unsafe and can cause serious toxicity, including stomach upset, bleeding, and in rare cases life-threatening effects like dangerous heart rhythms or organ failure. Homeopathic forms (highly diluted) are generally well tolerated, but this is a liquid extract, not a homeopathic preparation, so swallowing it straight carries real risk.
Can I use this while pregnant or breastfeeding?
Not enough safety data exists to say it's okay during pregnancy or breastfeeding. The current guidance is to avoid it. Talk with your doctor or pharmacist about your situation before using this product.
Does arnica actually work for osteoarthritis?
Arnica is rated possibly effective for osteoarthritis, meaning there is some supporting evidence—but it's not a slam dunk. You may see a benefit, but results aren't guaranteed. If you're interested in trying it, talk it over with your doctor first, especially if you're on any blood-thinning medications.
What are the most common side effects?
When used in homeopathic or very dilute amounts, arnica is generally well tolerated. In stronger oral doses, it can cause nausea, vomiting, stomach pain, diarrhea, drowsiness, nervousness, and headache. If applied to skin, contact dermatitis or irritation may occur.
Does this interact with aspirin or other blood thinners?
Yes. Arnica contains compounds that may reduce platelet aggregation (how sticky your blood is), which could add to the blood-thinning effect of drugs like warfarin, clopidogrel, and aspirin, raising your bleeding risk. Check with your doctor or pharmacist before starting if you're on any of these medications.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Arnica label
Go deeper

The Full Monographs Behind Arnica’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Arnica

Interacts with 122 drugs

Arnica is a daisy-family plant used mainly in topical and homeopathic products for bruising, muscle soreness, and pain. The evidence is mixed and mostly weak, and undiluted arnica taken by m...

Read the full Arnica monograph →
Sources

Sources & How We Checked

Arnica's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 10 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Arnica 10 references
  1. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  2. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  3. Schroder H, Losche W, Strobach H, et al. Helenalin and 11 alpha, 13-dihydrohelenalin, two constituents from Arnica montana L., inhibit human platelet function via thiol-dependent pathways. Thromb Res 1990;57:839-45.
  4. Adkison JD, Bauer DW, Chang T. The effect of topical arnica on muscle pain. Ann Pharmacother 2010;44:1579-84. PubMed
  5. No authors listed. Final report on the safety assessment of Arnica montana extract and Arnica montana. Int.J.Toxicol. 2001;20:1-11. DOI
  6. Karow JH, Abt HP, Frohling M, and Ackermann H. Efficacy of Arnica montana D4 for healing of wounds after Hallux valgus surgery compared to diclofenac. J Altern Complement Med 2008;14:17-25.
  7. Venkatramani DV, Goel S, Ratra V, et al. Toxic optic neuropathy following ingestion of homeopathic medication Arnica-30. Cutan.Ocul.Toxicol. 2013;32:95-97. PubMed
  8. Moghadam BK, Gier R, and Thurlow T. Extensive oral mucosal ulcerations caused by misuse of a commercial mouthwash. Cutis 1999;64:131-134.
  9. Stevinson C, Devaraj VS, Fountain-Barber A, et al. Homeopathic arnica for prevention of pain and bruising: randomized placebo-controlled trial in hand surgery. J R Soc Med 2003;96:60-65. PubMed
  10. Canders CP, Stanford SR, Chiem AT. A dangerous cup of tea. Wilderness Environ Med. 2014 Mar;25(1):111-2. PubMed

See these in context on the Arnica monograph →

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

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