Sclerotherapy is a medical procedure used to eliminate varicose veins and spider veins. Sclerotherapy involves an injection of a solution (called a sclerosant) directly into the vein. The solution irritates the lining of the blood vessel, causing it to swell and stick together. Over time, the vessel turns into scar tissue that fades from view.
Sclerotherapy is a well-proven procedure and has been in use since the 1930s.
WebMD. (2008, February 28). Retrieved from http://www.webmd.com/skin-beauty/guide/cosmetic-procedures-sclerotherapy