Sclerotherapy is a medical procedure, performed to treat the spider veins and varicose veins. Varicose veins are twisted, swollen and painful, blood-filled veins. Sclerotherapy is not mandatory for the patients and is done after the consultation between a patient and the physician. During this procedure, the doctor injects a solution into the veins of the patient directly. This solution, used during sclerotherapy, causes the scarring and collapsing of the veins, which further pushes the blood into the healthy veins. The affected veins get collapsed and absorbed by the surrounding tissue, and slowly fade away. This fading away of the affected veins may take a few weeks and sometimes, the complete results might be observed in a month. Usually, the varicose veins are found in the legs and are blue in color. Normally, the valves present in the veins help the blood flow to the heart, preventing the blood to collect in a single area. However, in the case of varicose veins, these valves get damaged, resulting in filling up of the veins, at a single place, with blood. This collection of blood is common when a person is standing.