Sclerotherapy is the injection of a substance into unwanted veins to cause their destruction and eventual removal by the body. It is commonly used to treat varicose veins of the legs. Typically, two to three treatment sessions are required to achieve a 50% to 95% improvement. Treatment sessions typically last about 20 minutes and are spaced approximately six weeks apart.

Although there are lasers available to treat varicose veins, sclerotherapy continues to be the most effective treatment.