Haemorrhoids are variceal dilatations of the anal and perianal venous plexus and often develop secondary to the persistently elevated venous pressure within the haemorrhoidal plexus (Kumar 2005). Phlebotonics are a heterogenous class of drugs consisting of plant extracts (i.e. flavonoids) and synthetic compounds (i.e. calcium dobesilate). Although their precise mechanism of action has not been fully established, they are known to improve venous tone, stabilize capillary permeability and increase lymphatic drainage. They have been used to treat a variety of conditions including chronic venous insufficiency, lymphoedema and haemorrhoids.
Numerous trials assessing the effect of phlebotonics in treating the symptoms and signs of haemorrhoidal disease suggest that there is a potential benefit.