Troxerutin is a flavonoid derivative used primarily for its vasoprotective properties, particularly in the support and treatment of capillary weakness and chronic venous insufficiency. There is moderate scientific evidence supporting its efficacy: several clinical studies and reviews have reported that troxerutin can improve capillary resistance, decrease capillary permeability, and reduce symptoms associated with fragile or "leaky" capillaries, such as edema, bruising, and microcirculatory disturbances.

The mechanism of action is believed to involve antioxidant activity, inhibition of platelet aggregation, and stabilization of vascular endothelium, which together help strengthen capillary walls and reduce inflammation. Notably, troxerutin has been compared with other established vasoactive drugs in randomized controlled trials, showing similar effectiveness in reducing symptoms like swelling and discomfort in conditions such as chronic venous insufficiency and diabetic microangiopathy.

While the overall quality and number of large-scale, high-quality randomized controlled trials is limited, the available evidence from both human and animal studies provides a reasonable scientific basis for the use of troxerutin in capillary weakness. It is approved and commonly used for this indication in several European and Asian countries.