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Dietary supplement

Horse Chestnut Ingredients & Drug Interactions

by Herb Pharm

Horse Chestnut label
See full label image
Liquid Category: Botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Horse Chestnut 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

Horse Chestnut is a dietary supplement by Herb Pharm with 1 active ingredient. Its ingredients are commonly taken for chronic venous insufficiency, leg swelling and heaviness, varicose veins.Based on those ingredients, 122 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Horse Chestnut seed (Aesculus hippocastanum) 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 Horse Chestnut by Herb Pharm

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

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HelloPharmacist Scorecard of Horse Chestnut 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 11, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: a liquid extract made from horse chestnut seeds. The extract has had the toxic constituent esculin removed during processing.

The liquid also includes two inactive ingredients — certified organic cane alcohol and distilled water — which serve as the base for the extract.

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: Circulatory support and leg vein health.
  • We looked for evidence on: Chronic venous insufficiency (CVI), Hemorrhoids, Postoperative swelling, Varicose veins, Leg swelling, Venous insufficiency.
  • The strongest evidence on file: Horse Chestnut is rated "Possibly Effective" for Chronic venous insufficiency (CVI) (Natural Medicines).
  • Also on file: Horse Chestnut is rated "Insufficient Reliable Evidence To Rate" for Hemorrhoids, Postoperative swelling.

Horse chestnut seed extract is possibly effective for chronic venous insufficiency (CVI) — a condition where blood pools in the veins of the legs, causing swelling, pain, and heaviness. For hemorrhoids, kidney stones, and irritable bowel syndrome, the evidence we hold isn't established enough to rate how well it works.

The evidence, ingredient by ingredient Horse Chestnut

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.

Properly processed horse chestnut seed extract is generally well tolerated when taken by mouth. The most common side effects reported in trials are dizziness, stomach upset, headache, and itching.

A thorough safety evaluation hasn't been completed, so some rare events may not be well documented. One case report describes a heart complication (pericardial effusion) in someone who consumed large amounts of horse chestnut paste, though causation wasn't certain.

Calf spasms have also been reported in patients with CVI using the extract. The safety data advises against use during pregnancy and breastfeeding — there isn't enough information to know it's safe in either situation.

Raw plant parts are toxic and shouldn't be used; only processed seed extract should be taken.

Side effects, ingredient by ingredient Horse Chestnut

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 — Horse Chestnut.
  • 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, double-check with your pharmacist if you're on any blood thinners or antiplatelet drugs — that's where the documented interaction risk sits. These include medications like warfarin, apixaban, aspirin, and clopidogrel, among others in those classes.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

If you have leg swelling or heaviness from venous insufficiency and aren't on blood thinners or antiplatelet drugs, this extract may be worth discussing with your pharmacist. If you take any blood thinner or antiplatelet medication, check with us first — the bleeding risk matters.

Pregnant or nursing? Skip it and talk with your doctor about other options.

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 Dec 21, 2024.

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 Horse Chestnut, straight from the product label.

Brand Herb Pharm
Barcode (UPC) 090700000691
Net contents 1 Fluid Ounce(s); 30 mL
Market status On market
Date entered into DSLD Dec 21, 2024
DSLD ID 302475
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 Horse Chestnut 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:
0.7 mL
Maximum serving Sizes:
0.7 mL
Servings per container
42
UPC/BARCODE
090700000691
IngredientAmount% DV
Horse Chestnut seed (Aesculus hippocastanum) extract651 mg--

Other ingredients: certified organic Cane Alcohol, distilled Water

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 Adults: Add 1 squeeze of the dropper bulb to 2 oz. of water or juice, 2 or 3 times per day. Best taken between meals.

Precautions

Keep out of the reach of children.

Storage

Store away from heat & light

Formulation

Aesculus hippocastanum

System restoration Cardio & circulatory

Gluten-free

FDA Statement of Identity

Herbal Supplement

Formula

Horse chestnut liquid extract

FDA Disclaimer Statement

This statement has 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

Horse Chestnut by Herb Pharm label

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

Horse Chestnut 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 Horse Chestnut by Herb Pharm

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

Serving size0.7 mL Dosage formLiquid Servings per container42 Amounts shown are per serving.

Horse Chestnut seed (Aesculus hippocastanum) extract

Interacts with
122 drugs
651 mg per serving

Horse chestnut seed extract is most often used for chronic venous insufficiency, where standardized products may help reduce leg swelling, pain, and h...

Horse Chestnut seed (Aesculus hippocastanum) extract monograph & interactions

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

Interaction report

Horse Chestnut by Herb Pharm Drug Interactions

Want to check YOUR meds against Horse Chestnut?

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

Horse Chestnut seed (Aesculus hippocastanum) extract 122

Individual Drug Interactions

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

1 of the 1 ingredient in Horse Chestnut interact with drugs. Each result below shows which ingredient is responsible. Horse Chestnut seed (Aesculus hippocastanum) extract

Each ingredient & the kinds of drugs it affects

For each ingredient in Horse Chestnut 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.

Horse Chestnut seed (Aesculus hippocastanum) extract1 drug type · 122 drugs

Anticoagulant/Antiplatelet Drugs

Horse chestnut may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Horse chestnut contains the constituent esculin which has been shown to have antithrombotic effects. Therefore, horse chestnut might have antiplatelet effects. This has not been shown in humans.

Likelihood Possible Evidence D
Horse Chestnut seed (Aesculus hippocastanum) extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Horse Chestnut, 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

Horse Chestnut by Herb Pharm: Common Questions

Does Horse Chestnut by Herb Pharm interact with any medications?
Yes. Based on its ingredients, Horse Chestnut 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?
Horse Chestnut 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.
Can I take this if I'm pregnant or breastfeeding?
No. The safety data advises against it during pregnancy, and safety hasn't been established for breastfeeding either. Talk with your doctor about what's safe for you.
What side effects have been reported?
The most common are dizziness, stomach upset, headache, and itching. A thorough safety review hasn't been done, so rare events may not be fully documented. One case reported a heart complication, though it wasn't certain the supplement caused it.
What is horse chestnut actually used for?
It's possibly effective for chronic venous insufficiency — the leg swelling, pain, and heaviness that comes from blood pooling in leg veins. For hemorrhoids, kidney stones, and IBS, we don't have enough evidence to say how well it works.
Is the raw plant safe to use?
No. Raw horse chestnut parts are toxic. This product uses a properly processed seed extract with the toxic part removed, which is the safe form to take.
Does this thin the blood?
Lab studies show the extract may have blood-thinning effects, but this hasn't been proven in people. That's why it can increase bleeding risk if you're already on a blood thinner or antiplatelet drug.

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.

Horse Chestnut label
Go deeper

The Full Monographs Behind Horse Chestnut’s Ingredients

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

Herb & supplement monograph

Horse Chestnut

Interacts with 122 drugs

Horse chestnut seed extract is most often used for chronic venous insufficiency, where standardized products may help reduce leg swelling, pain, and heaviness. Raw, unprocessed horse chestnu...

Read the full Horse Chestnut monograph →
Sources

Sources & How We Checked

Horse Chestnut'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 21 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.

Horse Chestnut 21 references
  1. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
  2. Ellenhorn MJ, et al. Ellenhorn's Medical Toxicology: Diagnoses and Treatment of Human Poisoning. 2nd ed. Baltimore, MD: Williams & Wilkins, 1997.
  3. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  4. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  5. Greeske K, Pohlmann BK. Horse chestnut seed extract-an effective therapy principle in general practice. Drug therapy of chronic venous insufficiency. Fortschr Med 1996;114:196-200.
  6. Robbers JE, Tyler VE. Tyler's Herbs of Choice: The Therapeutic Use of Phytomedicinals. New York, NY: The Haworth Herbal Press, 1999.
  7. Takegoshi K, Tohyama T, Okuda K, et al. A case of Venoplant-induced hepatic injury. Gastroenterol Jpn 1986;21:62-5.
  8. Jaspersen-Schib R, Theus L, Guirguis-Oeschger M, et al. [Serious plant poisonings in Switzerland 1966-1994. Case analysis from the Swiss Toxicology Information Center]. Schweiz Med Wochenschr 1996;126:1085-98.
  9. Popp W, Horak F, Jager S, et al. Horse chestnut (Aesculus hippocastanum) pollen: a frequent cause of allergic sensitization in urban children. Allergy 1992;47:380-3.
  10. Diaz-Perales A, Collada C, Blanco C, et al. Cross-reactions in the latex-fruit syndrome: A relevant role of chitinases but not of complex asparagine-linked glycans. J Allergy Clin Immunol 1999;104:681-7. PubMed
  11. Blanco C, Diaz-Perales A, Collada C, et al. Class I chitinases as potential panallergens involved in the latex-fruit syndrome. J Allergy Clin Immunol 1999;103:507-13. PubMed
  12. Comaish JS, Kersey PJ. Contact dermatitis to extract of horse chestnut (esculin). Contact Dermatitis 1980;6:150-1. PubMed
  13. Pittler MH, Ernst E. Horse chestnut seed extract for chronic venous insufficiency (Cochrane Review). In: The Cochrane Library, Issue 3, 2004. Chichester, UK: John Wiley & Sons, Ltd. PubMed
  14. Ottillinger, B. and Greeske, K. Rational therapy of chronic venous insufficiency--chances and limits of the therapeutic use of horse-chestnut seeds extract. BMC.Cardiovasc.Disord. 2001;1(1):5. PubMed
  15. Pittler, M. H. and Ernst, E. Horse chestnut seed extract for chronic venous insufficiency. Cochrane.Database.Syst.Rev. 2004;(2):CD003230. PubMed
  16. Fang, Y., Zhao, L., Yan, F., Xia, X., Xu, D., and Cui, X. Escin improves sperm quality in male patients with varicocele-associated infertility. Phytomedicine. 2010;17(3-4):192-196. PubMed
  17. De Smet, P. A., Van den Eertwegh, A. J., Lesterhuis, W., and Stricker, B. H. Hepatotoxicity associated with herbal tablets. BMJ 7-13-1996;313(7049):92.
  18. Rehn, D., Unkauf, M., Klein, P., Jost, V., and Lucker, P. W. Comparative clinical efficacy and tolerability of oxerutins and horse chestnut extract in patients with chronic venous insufficiency. Arzneimittelforschung 1996;46(5):483-487.
  19. Edem E, Kahyaoglu B, Çakar MA. Acute Effusive Pericarditis due to Horse Chestnut Consumption. Am J Case Rep. 2016;17:305-8. PubMed
  20. Costa Santos D, Lérias G, Madruga I. Drug-induced Liver Injury Due to a Horse Chestnut Dietary Supplement. Eur J Case Rep Intern Med 2021;8(3):002389. PubMed
  21. Yi HY, Lee JY. Poisoning due to consumption of horse chestnut seed. Clin Exp Emerg Med 2021;8(4):333-335. PubMed

See these in context on the Horse Chestnut 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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