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Horse Chestnut

How does Horse Chestnut work?

Horse chestnut contains a substance that thins the blood. It also makes it harder for fluid to leak out of veins and capillaries and weakly promotes fluid loss through the urine to help prevent water retention (edema).

Are there safety concerns?

Horse chestnut seems to be safe for most people when a standardized seed extract product is used short-term. Standardized products have been tested to contain exact amounts of a verified chemical. Look for products which have had the toxic substance esculin removed. Horse chestnut products can sometimes cause side effects such as dizziness, headache, stomach upset, and itching.

Pollen from the horse chestnut flower can cause allergic reactions. Rectal (suppository) use of horse chestnut may cause inflammation and itching in the anal area. Intravenous injection (IV) of horse chestnut seed extracts has caused kidney and liver damage.

Raw horse chestnut seed, bark, flower, and leaf are UNSAFE and poisonous when taken by mouth. Death can occur. Signs of poisoning include stomach upset, kidney problems, muscle twitching, weakness, loss of coordination, enlarged eye pupils, vomiting, diarrhea, depression, paralysis, and stupor. Accidental ingestion of horse chestnut requires prompt medical attention. Children have been poisoned by drinking a tea made from the leaves and twigs or eating seeds.

Horse chestnut might lower blood sugar. If you have diabetes, watch for signs of too low blood sugar (hypoglycemia) and check your blood sugar carefully.

Do not take horse chestnut if:
  • You are pregnant or breast-feeding.
  • You have a latex allergy.
  • You have a kidney disease.
  • You have a liver disease.

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

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Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.





Medical Dictionary