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What is horse chestnut?


Horse chestnut is an herbal remedy made from an extract of the seeds, bark, and leaves of the horse chestnut tree. For centuries it was used to treat various medical conditions, including varicose veins, poor circulation, stomach ulcers, and hemorrhoids. The U.S. Food and Drug Administration (FDA) does not recommend using horse chestnut for hemorrhoids, and studies have not proven its effectiveness in treating stomach ulcers.

Potential health benefits

Some medical research suggests that when taken by mouth, horse chestnut extract may be as effective as support stockings in reducing the leg swelling that goes along with poor circulation. It may take up to 12 weeks to see results with horse chestnut therapy, compared with four weeks for treatment with support stockings. Some people claim that horse chestnut therapy can improve the appearance of varicose veins, but it's not clear how well it really works.

Drug forms

Horse chestnut comes in capsules, gels, lotions, and ointments. For capsules, the usual dose is one 257-mg capsule containing 18 to 22% aescin, the active ingredient is aescin, but the dose varies widely. You take capsules with morning and evening meals. Be sure to follow directions on package labeling when using these products.

Potential side effects

Never eat unprocessed horse chestnuts taken from the tree, because they can cause nausea, vomiting, muscle twitching and weakness, and dilated pupils. With proper processing to remove the natural toxins, horse chestnut is relatively safe. Horse chestnut is generally well tolerated. The most common side effect is stomach upset. Rarely, allergic reactions may occur such as itching, runny nose, or even respiratory. There are reports of liver and kidney problems with use of horse chestnut.

People with bleeding disorders should not use horse chestnut products. Horse chestnut products contain chemicals that may thin the blood, and can raise the risk of bleeding. Horse chestnut can be very toxic, especially for children. Use caution, and always talk to your doctor before using herbs or alternative medicines.

Drug Interactions

Horse chestnut may potentially interact with blood thinners because horse chestnut contains chemicals that may thin the blood. Due to this interaction, do not use horse chestnut it if you take aspirin, warfarin (Coumadin®), ticlopidine (Ticlid®) or clopidogrel (Plavix®). Combining horse chestnut with these drugs may increase the risk of bleeding. Horse chestnut should also not be taken with anitdiabetic agents and diuretics.

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