What is horse chestnut

Horse chestnut is an herb prepared from the leaves or seeds of the horse chestnut tree (Aesculus hippocastanum L.), and is used primarily for complications of venous insufficiency including varicose veins, ankle swelling, leg cramps and hemorrhoid pain. Horse chestnut homeopathic product has not been evaluated by the US Food and Drug Administration (FDA) for safety or efficacy. FDA is not aware of scientific evidence to support homeopathy as effective.

Horse chestnut has been implicated in rare instances of clinically apparent liver injury.

The horse chestnut tree is native to the Balkan Peninsula (which includes such countries as Albania, Bulgaria, Greece, Romania, and Serbia), but has been introduced worldwide and is widely planted for its handsome shape and attractive leaves, nuts and flowers. The horse chestnut should not be confused with the California or Ohio chestnuts (Aesculus california and glabra), which are different species and more often called buckeye trees.

Usable parts of the horse chestnut plant include the seed, bark, and leaf, but seed extracts are most common. Historically, horse chestnut seed extract was used for joint pain, bladder and gastrointestinal problems, fever, and leg cramps. Today, people use horse chestnut extract as a dietary supplement for chronic venous insufficiency (when the veins of the lower leg are unable to send blood back toward the heart), hemorrhoids, and swelling after surgery. Preparations made from the tree’s bark are applied to skin sores.

Horse chestnut benefits

• A 2012 Cochrane systematic review ¹ of 17 studies published between 1976 and 2002 suggested that horse chestnut seed extract can improve leg pain, swelling, and itching in people with chronic venous insufficiency (e.g., varicose veins) when taken for a short time. Results from one of these studies suggested that horse chestnut seed extract may be as effective as wearing compression stockings.
• Preliminary evidence from one Chinese study ² suggested that aescin (escin), the main ingredient in horse chestnut, may help restore fertility in some men. However, since all the men in the study also received other supplements and drugs, it’s unclear whether the improvement was due to this compound alone or the combination approach.

Horse chestnut uses

Horse chestnut extract is used for the treatment of symptoms of varicose veins ³, hemorrhoids and phlebitis. Extracts of the horse chestnut seeds are also used for diarrhea, fever and urinary hesitancy. Creams with horse chestnut extract are used topically for muscle and joint aches due to arthritis or trauma. The constituents of horse chestnut extracts are many and include triterpene saponins, hydroxycoumarins, flavonoids, and tannins. Importantly, horse chestnut seeds contain the toxic triterpene saponin known as escin and its glycoside esculin. Commercial preparations remove the toxic saponins and are generally well tolerated. Horse chestnut is available as capsules, tablets, liquid extract, gels and solutions for parenteral administration.

Horse chestnut active components are aescin, phytosterol, flavonoids, tannins, and hydroxycoumarins ⁴. The most active component in horse chestnut, aescin ⁵, has anti-inflammatory and antiedematous features ⁶. Some researchers suggest that horse chestnut is a strong inhibitor of adenosine diphosphate – induced thrombocyte aggregation ⁷.  In 1999, German Commission E accepted the use of horse chestnut products for chronic venous insufficiency treatment ⁸. In 2004, Ruffini et al. ⁹ demonstrated that topical treatment containing aescin in gel form was very effective in improving skin perfusion and nutrition in patients with venous microangiopathy. In 2013, Gurel et al. ¹⁰ reported their research about an herbal cream for hemorrhoids on rats, which contained horse chestnut fruit along with some other herbs. Treatment with their herbal hemorrhoid cream demonstrated anti-inflammatory and antioxidant effects. In traditional medicine, horse chestnut has been consumed to improve cough and to cure rheumatism; however, these uses are not recommended because of their potential toxicity ¹¹.

Horse chestnut side effects

Horse chestnut side effects include nausea, dizziness, headache and pruritus.

The unprocessed seeds, leaves, bark, and flowers of horse chestnut contain esculin, which is poisonous and may increase the risk of bleeding. Escin (aescin), on the other hand, is a different compound and is considered to be safe.

Properly processing horse chestnut seed extract removes esculin. The processed extract is considered generally safe when used for short periods of time. However, the extract can cause some side effects, including itching, nausea, gastrointestinal upset, muscle spasm, or headache.

There was a case report of a 32-year-old male patient developing pericardial effusion (fluid around the sac of the heart) after consuming 3 boxes of unpurified, traditionally acquired horse chestnut paste (Aesculus hippocastanum L) over the previous 1.5 months ¹². The development of pericardial effusion after consumption of horse chestnut could be due to horse chestnut strong anti-thrombocyte aggregation feature ¹². Eating an entire horse chestnut that has not been purified is likely to have considerable side effects ⁶. Consuming unpurified, traditionally acquired horse chestnut paste this way, the antigen amount to which the body can react increases substantially. Another possible mechanism is that the production of antibodies as an immunologic response to these antigens might progress into a clinical condition that leads to pericardial effusion. Exudative effusion, such as was seen in this case, might have occurred within this inflammatory ground. This theory is supported by the negative results for the bioculture, malignancy, and rheumatologic markers.

Despite wide scale use, there have been few published instances of liver injury due to horse chestnut. In isolated cases of liver toxicity attributed to horse chestnut extracts, injury became apparent between 4 and 8 weeks after starting the herbal and were associated with either hepatocellular or mixed patterns of serum enzyme elevations and with a self-limited, rapidly resolving course. Immunoallergic and autoimmune features were not present or not mentioned.

The cause of liver injury attributed to horse chestnut extracts is unknown, but is likely to be idiosyncratic.

References

1. Pittler MH, Ernst E. Horse chestnut seed extract for chronic venous insufficiency. Cochrane Database of Systematic Reviews 2012, Issue 11. Art. No.: CD003230. DOI: 10.1002/14651858.CD003230.pub4 https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD003230.pub4/full
2. Fang Y, Zhao L, Yan F, et al. Escin improves sperm quality in male patients with varicocele-associated infertility. Phytomedicine. 2010;17(3-4):192-196. https://www.ncbi.nlm.nih.gov/pubmed/19682880
3. Bombardelli E, Morazzoni P, Griffini A. Aesculus hippocastanum L. Fitoterapia 1996;67(6):483‐511
4. Gruenwald J, et al., editors. PDR for Herbal Medicines. 3rd ed. Montvale, NJ: Thomson PDR; 2004. pp. 445–48.
5. Schrader E, Schwankl W, Sieder C, Christoffel V. Comparison of the bioavailability of beta‐aescin after single oral administration of two different drug formulations containing an extract of horse‐chestnut seeds [Vergleichende Untersuchung zur Bioverfügbarkeit von ß‐Aescin nach oraler Einmalverabreichung zweier Rosskastaniensamenextrakt enthaltender, galenisch unterschiedlicher Darreichungsformen]. Pharmazie 1995;50(9):623‐7.
6. Sirtori CR. Aescin: Pharmacology, pharmacokinetics and therapeutic profile. Pharmacol Res. 2001;44(3):183–93
7. Jagroop IA. Plant extracts inhibit ADP-induced platelet activation in humans: Their potential therapeutic role as ADP antagonists. Purinergic Signal. 2014;10(2):233–39.
8. Blumenthal M. Expanded Commission E Monographs. Boston: Integrative Medicine Publications; 2000.
9. Ruffini I, Belcaro G, Cesarone MR, Dugall M. Efficacy of topical treatment with aescin + essential phospholipids gel in venous insufficiency and hypertension. Angiology. 2004;55(Suppl.1):S19–21
10. Gurel E, Ustunova S, Ergin B, et al. Herbal haemorrhoidal cream for haemorrhoids. Chin J Physiol. 2013;56(5):253–62
11. Gruenwald J, et al., editors. PDR for Herbal Medicines. 3rd ed. Montvale, NJ: Thomson PDR; 2004. pp. 445–48.
12. Edem E, Kahyaoğlu B, Çakar MA. Acute Effusive Pericarditis due to Horse Chestnut Consumption. Am J Case Rep. 2016;17:305-8. Published 2016 May 4. doi:10.12659/AJCR.896790 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4913740