- Aesculus hippocastanum L.
- Aescin, aescine, Aesculaforce®, aescule, aesculetin, buckeye, bongay, chestnut, conkers, conquerors, coumarins, eschilo, escin, escina, escine, fatty acids, fish poison, flavonoids, graine de marronier d’Inde, fraxetin glucoside, fraxin, HCSC, H. vulgare Gaertnhestekastanje, Hippocastabi folium, Hippocastanaceae (family), Hippocastani semen, horsechestnut, horse chestnut seed extract, HCSE, linolenic acid, Marron Europeen, Marronier, NV-101, palmitic acid, quinines, Rokastaniensamen, rosskastanie, scopoletin glucoside, scopolin, Spanish chestnut, steric acid, sterols, tannins, Venastat®, Venoplant®, Venostasin®.
- Horse chestnut seed extract (HCSE) is widely used in Europe for chronic venous insufficiency (CVI), a syndrome that may include leg swelling, varicose veins, leg pain, itching, and skin ulcers. Although HCSE is traditionally recommended for a variety of medical conditions, CVI is the only condition for which there is strong supportive scientific evidence.
- Side effects from HCSE have been similar to placebo in clinical trials. However, due to an increased risk of low blood sugar, caution is advised in children and people with diabetes.
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
C – C
A – A
*Key to grades:
The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.
Adults (18 years and older)
- A dose of 300 milligrams every 12 hours, for up to 12 weeks (containing 50 to 75 milligrams of escin per dose), has been taken by mouth. A dose of 600 milligrams of chestnut seed extract per day has also been studied. One capsule of HCSE standardized to 50 mg of aescin for 12 weeks has also been used.
- A gel preparation of horse chestnut containing 2% escin (applied to the skin 3-4 times daily) has been studied for bruising, without clear benefits.
- Severe allergic reaction (anaphylactic shock) has been reported with intravenous use. Horse chestnut leaf has been associated with liver inflammation (hepatitis) after injection into muscle.
Children (younger than 18 years)
- There is not enough scientific evidence to recommend use of horse chestnut in children. Deaths have been reported in children who ate raw horse chestnut seeds or tea made from horse chestnut leaves and twigs.
The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.
- Horse chestnut seed extract (HCSE) may cause an allergic reaction in patients with known allergy to horse chestnuts, esculin, or any of its ingredients (flavonoids, biosides, trisides of quertins, and oligosacharides including 1-ketose and 2-ketose). Anaphylactic shock (severe allergic reaction) has been reported with intravenous (through the vein) use.
- Allergic skin rashes (contact dermatitis) have been reported after use of a skin cream containing horse chestnut seed extract.
Side Effects and Warnings
- Unprocessed horse chestnut seeds have been associated with significant toxicity and death. Symptoms associated with horse chestnut poisoning may include vomiting, diarrhea, headache, confusion, weakness, muscle twitching, poor coordination, coma, or paralysis. Horse chestnut seed extract (HCSE) standardized to escin content should not contain significant levels of esculin and should not have the same risks.
- Standardized HCSE is generally considered to be safe in adults at recommended doses for short periods of time. Stomach upset, muscular (calf) spasm, headache, heartburn, vomiting, diarrhea, dizziness, nausea, and itching have been reported. Contact skin irritation (dermatitis) has been reported following application of HCSE to the skin.
- Based on animal study, HCSE may cause lowered blood sugar. Caution is advised in patients with diabetes or hypoglycemia, and in those taking drugs, herbs, or supplements that affect blood sugar. Serum glucose levels may need to be monitored by a qualified healthcare provider, and medication adjustments may be necessary.
- In theory, horse chestnut may increase the risk of bleeding. Caution is advised in patients with bleeding disorders or taking drugs that may increase the risk of bleeding. Monitoring is recommended and dosing adjustments may be necessary. Liver and kidney toxicity has been associated with horse chestnut. Aflatoxins, considered to be cancer-causing agents, have been identified in commercial skin products containing horse chestnut, but not in HCSE.
- Several studies report the development of pseudolupus (a syndrome characterized by recurrent fever, muscle pain, and lung and heart muscle inflammation) in patients taking Venocuran or Venopyronum, which contains phenopyrazone, horse chestnut extract, and cardiac glycosides. Because these are combination products, these effects may not be accounted for by horse chestnut alone.
Pregnancy and Breastfeeding
- There is not enough scientific research to recommend the safe use of horse chestnut or HCSE during pregnancy and breastfeeding.
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Interactions with Drugs
- In theory, due to its esculin constituents, horse chestnut (but not horse chestnut seed extract, which when properly prepared does not contain esculin) may theoretically increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants (“blood thinners”) such as warfarin (Coumadin®) or heparin, anti-platelet drugs such as clopidogrel (Plavix®), and non-steroidal anti-inflammatory drugs such as ibuprofen (Motrin®, Advil®) or naproxen (Naprosyn®, Aleve®).
- In theory, and based on limited animal study, horse chestnut seed extract (HCSE) may have an additive effect when taken with drugs that cause hypoglycemia (low blood sugar levels). Caution is advised when using medications that may also lower blood sugar. Patients taking drugs for diabetes by mouth or insulin should be monitored closely by a qualified healthcare provider. Medication adjustments may be necessary.
- Escin in HCSE may theoretically interfere with protein-bound drugs such as phenytoin (Dilantin®), warfarin (Coumadin®), or amiodarone (Cordarone®), although human evidence is lacking.
- HCSE has been demonstrated to have antiangiogenic activity, and may thus interact with antiangiogenic drugs.
Interactions with Herbs and Dietary Supplements
- In theory, due to its esculin constituents, horse chestnut (but not horse chestnut seed extract, which when properly prepared does not contain esculin) may theoretically increase the risk of bleeding when taken with herbs or supplements that increase the risk of bleeding. Multiple cases of bleeding have been reported with the use of Ginkgo biloba, and fewer cases with garlic and saw palmetto. Numerous other agents may theoretically increase the risk of bleeding, although this has not been proven in most cases.
- In theory, and based on limited animal study, horse chestnut seed extract may have an additive effect when taken with other herbs or supplements that may lower blood sugar. Blood glucose levels may require monitoring, and doses may need adjustment.
- In theory, horse chestnut may interact with neurologic herbs and supplements.
Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.
- This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration ().
- Bassler D, Okpanyi S, Schrodter A, et al. Bioavailability of beta-aescin from horse chestnut seed extract: comparative clinical studies of two Galenic formulations. Adv Ther 2003 Sep-Oct;20(5):295-304.
- Bielanski TE, Piotrowski ZH. Horse-chestnut seed extract for chronic venous insufficiency. J Fam Pract 1999 Mar;48(3):171-2.
- Comaish JS, Kersey PJ. Contact dermatitis to extract of horse chestnut (esculin). Contact Dermatitis 1980 Jan;6(2):150-1.
- Diehm C, Trampisch HJ, Lange S, et al. Comparison of leg compression stocking and oral horse-chestnut seed extract therapy in patients with chronic venous insufficiency. Lancet 2-3-1996;347(8997):292-294.
- Diehm C, Vollbrecht D, Amendt K, et al. Medical edema protection–clinical benefit in patients with chronic deep vein incompetence. A placebo controlled double blind study. Vasa 1992;21(2):188-192.
- Ernst E, Pittler MH, Stevinson C. Complementary/alternative medicine in dermatology: evidence-assessed efficacy of two diseases and two treatments. Am J Clin Dermatol 2002;3(5):341-8.
- Koch R. Comparative study of Venostasin and Pycnogenol in chronic venous insufficiency. Phytother Res 2002;16 Suppl 1:S1-5.
- Lange S, Freitag G, Trampisch HJ. Practical experience with the design and analysis of a three-armed equivalence study. Eur J Clin Pharmacol. 1998 Sep;54(7):535-40.
- Ottillinger B, 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.
- Pittler MH, Ernst E. Horse chestnut seed extract for chronic venous insufficiency. Cochrane Database Syst Rev 2006 Jan 25;(1):CD003230.
- Popp W, Horak F, Jager S, et al. Horse chestnut (Aesculus hippocastanum) pollen: a frequent cause of allergic sensitization in urban children. Allergy 1992 Aug;47(4 Pt 2):380-3.
- Rehn D, Unkauf M, Klein P, et al. Comparative clinical efficacy and tolerability of oxerutins and horse chestnut extract in patients with chronic venous insufficiency. Arzneimittelforschung 1996;46(5):483-487.
- Siebert U, Brach M, Sroczynski G, et al. Efficacy, routine effectiveness, and safety of horsechestnut seed extract in the treatment of chronic venous insufficiency. A meta-analysis of randomized controlled trials and large observational studies. Int Angiol 2002;21(4):305-315.
- Suter A, Bommer S, Rechner J. Treatment of patients with venous insufficiency with fresh plant horse chestnut seed extract: a review of 5 clinical studies. Adv Ther 2006 Jan-Feb;23(1):179-90.
- Vayssairat M, Debure C, Maurel A, et al. Horse-chestnut seed extract for chronic venous insufficiency. Lancet 4-27-1996;347(9009):1182.
Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to . Selected references are listed below.