Plant extract - Phytotherapy

Horse Chestnut

The chestnut tree bark: Anti-oedematous, venotonic and vascular anti-inflammatory

Latin name

Aesculus hippocastanum L.

Family

Sapindaceae

History & Botany

Horse chestnut is native to the Balkans and the Caucasus, where it grows naturally in mountain forests. Introduced to Western Europe in the 16th century for ornamental purposes, it rapidly spread through avenues and public gardens. Its misleading "Indian" name stems from a historical confusion among the first Ottoman botanists. Balkan populations had known of its medicinal properties for centuries: bark and dried seeds were used to treat rheumatism, coughs and circulatory disorders.

Aescin, the major active compound, was isolated and characterised in the 20th century: it is one of the first phytomedicines to have benefited from controlled clinical studies on venous insufficiency. Today, horse chestnut extract standardised for aescin is one of the most prescribed and best-studied plant venotonics in Europe, particularly in Germany where it is classified as a medicinal product.

Morphology

Large deciduous tree reaching 25 to 35 metres. Palmate leaves composed of 5 to 7 large characteristic leaflets. White or pink flowers in upright, highly decorative panicles in spring. Fruits: green spiny husks containing 1 to 3 shiny brown seeds (conkers), not to be confused with edible chestnuts.

Part used & extraction

The seed (kernel) and bark, by hydro-alcoholic extraction. The dry extract is standardised for total aescin (minimum 16 to 20%). The raw seed is orally toxic: only standardised extracts are used in phytotherapy.

Aesculus hippocastanum L.

Characteristic shiny brown seeds and spiny husks

Active compounds & biochemistry

Organoleptic properties

Appearance

Dried seed

Seeds shiny mahogany brown, ovoid, heavy. Seed powder beige to light brown, fine and slightly granular.

Colour

Dry extract / liquid

Powder beige-brown to ochre-brown. Liquid extract: amber to red-brown, translucent, slightly foaming when shaken (saponins).

Odour

Dried seed & extract

Weak to moderate. Woody and slightly tannic notes, reminiscent of fresh bark. Slightly acrid at high concentration.

Taste

Extract in solution

Bitter, acrid and astringent, with a slightly pungent note typical of saponins. Persistent and slightly irritating aftertaste at high doses.

Solubility

Dry extract

Fine powder, good solubility in hydro-alcoholic medium and hot water. Saponins confer a strong characteristic foaming effect in agitated aqueous solution.

Medicinal properties & traditional use

Powerful anti-oedematous

Reduces venous oedema of the lower limbs. Efficacy comparable to elastic compression in several randomised clinical studies. Rapid action on swollen ankles and feet.

Chronic venous insufficiency

Improves CVI symptoms: heavy legs, pain, nocturnal cramps, itching and limb fatigue. Recognised by the German Commission E and the EMA as a treatment for mild to moderate CVI.

Haemorrhoids & varicose veins

Reduces haemorrhoidal inflammation, pain and bleeding. Improves varicose vein tone and slows their progression. Used orally and topically (gels, creams).

Vascular anti-inflammatory

Inhibits vascular inflammatory mediators (prostaglandins, cytokines). Protects the capillary wall against oxidative damage. Useful in the prevention of bruising and capillary fragility.