Common Names: horse chestnut, buckeye, Spanish chestnut
Latin Names: Aesculus hippocastanum
- Horse chestnut is a tree native to parts of southeastern Europe. Its fruits contain seeds that resemble sweet chestnuts but have a bitter taste.
- Historically, horse chestnut seed extract was used for joint pain, bladder and gastrointestinal problems, fever, leg cramps, and other conditions.
- Today, horse chestnut seed extract is promoted for chronic venous insufficiency (CVI; poor blood flow in the veins of the legs, which may lead to leg pain, swelling, itchiness, and other symptoms), irritable bowel syndrome, male infertility, and other conditions.
How Much Do We Know?
- Some studies in people have looked at horse chestnut seed extract for CVI, but very little research has been done on its use for other conditions.
What Have We Learned?
- A 2012 systematic review of 17 studies suggested that horse chestnut seed extract can improve symptoms of CVI. Results from one of these studies suggested that horse chestnut seed extract may be as effective as wearing compression stockings. The reviewers noted, however, that there is a need for more rigorous, large-scale randomized controlled trials to assess the efficacy of this treatment option for CVI.
- Small amounts of research have been done on horse chestnut seed extract for male infertility associated with varicocele (a swelling of veins inside the scrotum) and for irritable bowel syndrome, but there’s not enough information to draw definite conclusions about its effects on either condition.
What Do We Know About Safety?
- The raw seeds, bark, flowers, and leaves of horse chestnut are unsafe because they contain a toxic component. Standardized horse chestnut seed extracts, from which this component has been removed, appear to be safe for short-term use.
- Horse chestnut seed extracts are generally well tolerated but may cause side effects such as dizziness, nausea, and digestive upsets in some people.
- Little is known about whether it’s safe to use horse chestnut seed extract during pregnancy or while breastfeeding. No one—including women who are pregnant or breastfeeding—should consume raw horse chestnut.
Keep in Mind
- Take charge of your health—talk with your health care providers about any complementary health approaches you use. Together, you can make shared, well-informed decisions.
The NCCIH Clearinghouse provides information on NCCIH and complementary and integrative health approaches, including publications and searches of Federal databases of scientific and medical literature. The Clearinghouse does not provide medical advice, treatment recommendations, or referrals to practitioners.
Toll-free in the U.S.: 1-888-644-6226
tty (for deaf and hard-of-hearing callers):
Email: email@example.com (link sends email)
A service of the National Library of Medicine, PubMed® contains publication information and (in most cases) brief summaries of articles from scientific and medical journals. For guidance from NCCIH on using PubMed, see How To Find Information About Complementary Health Approaches on PubMed.
Office of Dietary Supplements (ODS), National Institutes of Health (NIH)
ODS seeks to strengthen knowledge and understanding of dietary supplements by evaluating scientific information, supporting research, sharing research results, and educating the public. Its resources include publications (such as Dietary Supplements: What You Need To Know) and fact sheets on a variety of specific supplement ingredients and products (such as vitamin D and multivitamin/mineral supplements).
Email: firstname.lastname@example.org (link sends email)
- Aesculus hippocastanum (Horse chestnut). Alternative Medicine Review. 2009;14(3):278-283.
- 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.
- Hawrelak JA, Wohlmuth H, Pattinson M, et al. Western herbal medicines in the treatment of irritable bowel syndrome: a systematic review and meta-analysis. Complementary Therapies in Medicine. 2020;48:102233.
- Horse chestnut. Natural Medicines website. Accessed at naturalmedicines.therapeuticresearch.com/ on January 22, 2020. [Database subscription]
- Pittler MH, Ernst E. Horse chestnut seed extract for chronic venous insufficiency. Cochrane Database of Systematic Reviews. 2012;11:CD003230. Accessed at https://www.thecochranelibrary.com on March 4, 2020.
This publication is not copyrighted and is in the public domain. Duplication is encouraged.
NCCIH has provided this material for your information. It is not intended to substitute for the medical expertise and advice of your health care provider(s). We encourage you to discuss any decisions about treatment or care with your health care provider. The mention of any product, service, or therapy is not an endorsement by NCCIH.