Sclerotherapy treatment uses a chemical solution known as a sclerosing agent. This is injected at a number of points that run alongside the thread vein.
The sclerosing agent works to irritate the lining of the veins, which when combined with compression of the leg after treatment; causes the walls of the vein to collapse. Over time, the thread veins will then be absorbed by the body. Multiple treatments will be required to achieve the best results, but sclerotherapy can be very effective in reducing the appearance of most spider veins and some small varicose veins significantly.
In most cases sclerotherapy is performed with a concentrated saline solution however other chemical solutions or special foam may be used if the vein is larger such as a varicose vein.