Diosmin is one of the most commonly used active substances in chronic venous insufficiency for its documented vasotrophic and anti-inflammatory activity. Diosmin is a molecule known for the vasotrophic efficacy, part of the flavonoid glycoside family. The molecule determines an increase in venous tone through the reduction of norepinephrine catabolism, with consequent strengthening of its physiological effect and therefore an increase in the duration of the vasoconstrictive action. It interferes with the inflammatory phenomena through different mechanisms: reduction of the production and release of the inflammatory mediators of the complement action of inactivation of free radicals. In the pathogenesis of the venous vascular damage, the inflammation is responsible for the increased permeability, diminished capillary resistance and istolesività. The anti-inflammatory properties of diosmin contribute to the protective action on the microcirculation. The action is determined by the blockage of cyclo-oxygenases from the inhibition of prostaglandin and thromboxane synthesis. In addition, diosmin inhibits the degradation of intracellular AMP, resulting in a lower release of inflammatory mediators, prostaglandins and free radicals in polymorphonuclear and macrophages. The antiedemigenous effect of diosmin is expressed by reducing permeability and capillary fragility and increasing lymphatic drainage. Diosmin determines an improvement in the circulation as: reduces capillary impermeability main cause of idiopathic cyclic edema decreases the fragility and increases the capillary resistance, since belonging to the vitamin P group has a capillaroprotective activity that occurs with the decrease of skin bleeding phenomena -much like purple, bruises. In patients with capillary fragility treated with diosmin, higher pressures are necessary than in untreated patients to determine bleeding lesions. The activity of the molecule on the lymphatic system is expressed by the increase, in frequency and amplitude, of the contractions in the capillaries and lymphatic collectors. The increased peristalsis involves an increase in the flow and therefore in the lymphatic flow. There is evidence that these activities are due to an interference on the metabolism of norepinephrine as well as on the sodium-potassium pump and calcium channels, which intervene on the automatism of muscle contractionDiosmin is well tolerated and there are no reports of significant side effects and can also be used in elderly patients in polytherapy Extract from: eighth National Scientific Assembly: Chronic diseases and fragile patients: areas of intervention of family medicine