Horse Chestnut

Introduction

This fact sheet provides basic information about horse chestnut-common names, uses, potential side effects, and resources for more information. Horse chestnut trees are native to the Balkan Peninsula (for example, Greece and Bulgaria), but grow throughout the Northern Hemisphere. Although horse chestnut is sometimes called buckeye, it should not be confused with the Ohio or California buckeye trees, which are related but not the same species.

Common Names

horse chestnut, buckeye, Spanish chestnut

Latin Names

Aesculus hippocastanum

What It Is Used For

• For centuries, horse chestnut seeds, leaves, bark, and flowers have been used for a variety of conditions and diseases.
• Horse chestnut seed extract has been used to treat chronic venous insufficiency (a condition in which the veins do not efficiently return blood from the legs to the heart). This condition is associated with varicose veins, pain, ankle swelling, feelings of heaviness, itching, and nighttime leg cramping.
• The seed extract has also been used for hemorrhoids.

How It Is Used

Horse chestnut seed extract standardized to contain 16 to 20 percent aescin (escin), the active ingredient, is the most commonly used form. Topical preparations have also been used.

What the Science Says

• Small studies have found that horse chestnut seed extract is beneficial in treating chronic venous insufficiency and is as effective as wearing compression stockings.
• There is not enough scientific evidence to support the use of horse chestnut seed, leaf, or bark for any other conditions.

Side Effects and Cautions

• Homemade preparations of horse chestnut should not be used. Raw horse chestnut seeds, leaves, bark, and flowers contain esculin, which is poisonous.
• When properly processed, horse chestnut seed extract contains little or no esculin and is considered generally safe. However, the extract can cause some side effects, including itching, nausea, or gastrointestinal upset.
• Tell your health care providers about any complementary and alternative practices you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care.

Sources

• Horse chestnut. Natural Medicines Comprehensive Database Web site. Accessed July 5, 2007.
• Horse chestnut. Natural Standard Database Web site. Accessed July 3, 2007.
• Horse chestnut seed extract. In: Blumenthal M, Goldberg A, Brinckman J, eds. Herbal Medicine Expanded Commission E Monographs. Newton, MA: Lippincott Williams & Wilkins; 2000:201-204.
• NCCAM National Institutes of Health