[Effects of horse-chestnut seed extract on transcapillary filtration in chronic venous insufficiency].

The effect of horse-chestnut seed extract (standardized on aescin; Venostasin retard) was assessed in a randomized placebo-controlled crossover double-blind trial of 22 patients with proven chronic venous insufficiency by measuring the capillary filtration coefficient and the intravascular volume of the lower leg by venous-occlusion plethysmography. Three hours after taking two capsules of Venostasin (600 mg; each capsule containing 50 mg aescin) the capillary filtration coefficient had decreased by 22%, whereas after administration of an identical-looking placebo capsule it rose but slightly over three hours. The difference in the effect of Venostasin and placebo is statistically significant (P = 0.006). The intravascular volume was reduced 5% more after Venostasin than the placebo, but this is not statistically significant. It is concluded that Venostasin has an inhibitory effect on oedema formation via a decrease in transcapillary filtration and thus improves oedema-related symptoms in venous diseases of the legs.