Horse chestnut is a plant also known as Aescin, Aesculus hippocastanum, Buckeye, Castaño de Indias, Châtaignier de Mer, Châtaignier des Chevaux, Escine, Faux-Châtaignier, Hippocastani, Hippocastanum Vulgare Gaertn, Marron Europeen, Marronnier, Spanish Chestnut, Venostasin Retard, Venostat, White Chestnut, and other names.

Horse chestnut has been used in alternative medicine and is likely effective in treating some symptoms of chronic venous insufficiency (decreased blood flow return from the feet and legs back to the heart). These symptoms include leg pain or tenderness, varicose veins, itching or swelling in the legs, and fluid retention (puffy or swollen ankles or feet).

Other uses not proven with research have included fever, cough, diarrhea, hemorrhoids, enlarged prostate, menstrual cramps, and swelling caused by arthritis, sprains, or bone fractures.

It is not certain whether horse chestnut is effective in treating any medical condition. Medicinal use of this product has not been approved by the FDA. Horse chestnut should not be used in place of medication prescribed for you by your doctor.

Horse chestnut is often sold as an herbal supplement. There are no regulated manufacturing standards in place for many herbal compounds and some marketed supplements have been found to be contaminated with toxic metals or other drugs. Herbal/health supplements should be purchased from a reliable source to minimize the risk of contamination.

Horse chestnut may also be used for purposes not listed in this product guide.

Follow all directions on the product label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

When considering the use of herbal supplements, seek the advice of your doctor. You may also consider consulting a practitioner who is trained in the use of herbal/health supplements.

If you choose to use horse chestnut, use it as directed on the package or as directed by your doctor, pharmacist, or other healthcare provider. Do not use more of this product than is recommended on the label.

The usual dose of horse chestnut in capsule form is 1 capsule every 12 hours before a meal.

Take the capsule with a full glass of water.

Do not crush, chew, break, or open a horse chestnut capsule. Swallow it whole.

It is best to use a horse chestnut product that contains an exact amount of the labeled chemical. Check the label to be sure your product does not contain a toxic substance called "esculin."

It may take up to 4 weeks before your symptoms improve. Call your doctor if your symptoms do not improve, or if they get worse while using horse chestnut.

Store at room temperature away from moisture, heat, and light.

Before using horse chestnut, talk to your healthcare provider. You may not be able to use horse chestnut if you have certain medical conditions, such as:

• a bleeding or blood clotting disorder (horse chestnut can thin your blood);

• diabetes (horse chestnut may cause low blood sugar);

• kidney disease;

• liver disease;

• a stomach or intestinal disorder;

• congestive heart disease;

• epilepsy;

• asthma;

• migraine headaches; or

• if you are allergic to latex.

It is not known whether horse chestnut will harm an unborn baby. Do not use this product if you are pregnant.

Horse chestnut may pass into breast milk and may harm a nursing baby. Do not use this product if you are breast-feeding a baby.

Do not give any herbal/health supplement to a child without medical advice.

Skip the missed dose if it is almost time for your next scheduled dose. Do not use extra horse chestnut to make up the missed dose.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. The use of raw horse chestnut (seeds, flowers, stems, leaves) can cause fatal poisoning.

Signs of horse chestnut poisoning may include weakness, depressed mood, loss of coordination, dilated pupils, vomiting, diarrhea, little or no urinating, muscle twitching, or loss of movement in any part of the body.

Avoid the use of raw horse chestnut seed, bark, flower, or leaves. These items are not safe to take by mouth and may cause fatal side effects.

Avoid using horse chestnut together with other herbal/health supplements that can lower blood sugar, such as alpha-lipoic acid, chromium, devil's claw, fenugreek, garlic, guar gum, Panax ginseng, psyllium, Siberian ginseng, and others.

Avoid using horse chestnut together with herbal/health supplements that can also affect blood-clotting. This includes angelica (dong quai), capsicum, clove, danshen, garlic, ginger, ginkgo, panax ginseng, poplar, red clover, turmeric, and willow.

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Although not all side effects are known, horse chestnut is thought to be possibly safe when taken for a short period of time.

Stop using horse chestnut and call your healthcare provider at once if you have:

• severe skin redness, swelling, itching, or rash.

Common side effects of horse chestnut may include:

• upset stomach;

• headache, dizziness; or

• itching

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Do not take horse chestnut without medical advice if you are using any of the following medications:

• insulin or oral diabetes medicine;

• medicines to prevent blood clots--clopidogrel (Plavix), dalteparin, enoxaparin, heparin, warfarin (Coumadin, Jantoven), and others; or

• an NSAID (nonsteroidal anti-inflammatory drug)--aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve), celecoxib, diclofenac, indomethacin, meloxicam, and others.

This list is not complete. Other drugs may interact with horse chestnut, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this product guide.