Sclerotherapy is the standard treatment for varicose and spider veins. A special sclerosing solution is injected into the dilated vein, which then collapses and is gradually absorbed by the body. By the end of the treatment program, the veins are less visible on the skin surface. This treatment requires 2-4 visits to provide optimal results. Sclerotherapy usually also relieves symptoms associated with enlarged veins and prevents further complications.