Hippocastanaceae



Common Trade Names

Horse Chestnut Extract, Horse Chestnut Power, Horse Chestnut SFSE, Venostasin Retard, Venostat

Common Forms

Capsules: 250 mg, 300 mg

Also available as extract using aescin to standardize concentration.

Source

The seeds from Aesculus hippocastanum are used to formulate horse chestnut extract sometimes known as Hippocastani semen. The bark of young branches should be used; the older bark is poisonous.

Chemical components

Horse chestnut is composed primarily of triterpene glycosides and flavonoids (quercetin, kaempferol, astragalin, isoquercetin, rutin), coumarins (aesculetin, fraxin, scopolin), allantoin, amino acids, choline, citric acid, and phytosterol. Products are adjusted to contain triterpene glycosides calculated as aescin (escin).

Actions

Anti-inflammatory actions have been documented for the saponins (aescin). Aescin reduces transcapillary filtration of water and protein and increases venous tone related to increased prostaglandin F 2 alpha (vasoconstrictor). Murine studies have demonstrated a reduction in vascular permeability from artificial insults (that is, acetic acid or histamine) after pretreatment with components of horse chestnut (escins, desaacylescins). Aescin stabilizes cholesterol­containing membranes of Iysosomes and limits the release of the enzymes. Usually, the release of the enzymes is increased in chronic pathological conditions of the vein. These enzymes normally break down the mucopolysaccharides in the cell membranes in the capillary walls, but this action is inhibited byaescin . Aescin has shown notable antiviral activity in vitro toward a strain of influenza VIrus.

Reported Uses

Horse chestnut therapy has been claimed to be effective for treating diarrhea, fever, hemorrhoids, phlebitis, and enlargement of the prostate gland. Some data exist to support a role in venous insufficiency.

Data also suggest a role for horse chestnut in treating varicose veins. Certain enzymes responsible for the metabolism of substances that regulate capillary rigidity and pore size were found to be reduced in patients with varicose veins treated with 900 mg of horse chestnut extract. Concentrations of these enzymes have been found to be elevated in patients with varicose veins and may playa role in this disorder .

Dosage

Dosages of 100 to 150 mg/day P.O. of the aescin component, given as a single dose or in divided doses b.i.d., have been clinically tested in humans.

Adverse Reactions

CV: shock.

GI: hepatotoxicity, nausea (with oral use), vomiting.

GU: nephropathy.

Hematologic: severe bleeding and bruising (caused by anti thrombotic activity of aesculin).

Musculoskeletal: muscle spasm.

Skin: hypersensitivity reactions, pruritus, urticaria.

Interactions

Anticoagulants, aspirin: Increased risk of bleeding because of aesculin, a hydroxycoumarin. Monitor the patient. Contraindications and precautions

Horse chestnut is contraindicated in pregnant or breast-feeding patients; effects are unknown. Use cautiously in patients who are hypersensitive to other members of the horse chestnut family and in those with bleeding disorders.

Special Considerations

The fruit, leaves, and older bark of horse chestnut are poisonous.

Monitor liver function test results.

Inform the patient and health care staff that horse chestnut may color urine red.

Instruct the patient to report fatigue, fever, unusual bleeding or bruising, and yellowing of skin or eyes.

Advise the patient to only use products derived from the seeds or bark of young branches.

Advise the patient to report changes in effectiveness of other drug therapies.

Urge the patient to check with his health care provider before taking other prescription or OTC drugs that may contain aspirin.

Points of Interest

Germany's Federal Institute for Drugs and Medical Devices recognizes horse chestnut extract as effective in treating chronic venous insufficiency.

Do not confuse horse chestnut with buckeye, also called horse chestnut.

Horse chestnut has been used I.V. in Europe for postoperative edema, presumably for its diuretic activity.

Commentary

Compression stocking therapy has been the primary treatment option

for chronic venous insufficiency, although patient compliance is generally poor. No allopathic drugs are indicated for treating this disorder. Standardized horse chestnut extracts or certain components (escins) have intriguing properties and may be useful in patients with symptoms associated with this disorder. Future studies should pursue this potential application. Of note, some data from previous controlled trials have examined parameters that might be considered subjective, such as fatigue, leg pain, pruritus, and tenseness. Additional large, randomized, double-blind, placebo-controlled trials that examine both efficacy and safety in a more objective manner are needed before horse chestnut or any of its components are given a definitive role in therapy.