Varicose and telangiectatic (spider) veins have existed ever since human beings assumed the upright position and gravity took hold. Pregnancy, prolonged sitting or standing, and heredity are the primary causes of these unsightly veins. Today, spider veins occur in an estimated eighty million adults in the United States. These small clusters of red, blue, or purple veins commonly occur on the thighs, calves, ankles, face, and trunk. Although troubling to many, these superficial veins are easily treated with sclerotherapy, which has been performed successfully for decades. Sclerotherapy is the gold standard for treating spider veins. Although other methods exist for vein removal, sclerotherapy is the best method for treating most superficial veins. Sclerotherapy is a virtually painless procedure and involves injecting a sclerosing agent into the vein through a tiny needle. The solution replaces the blood in the vein and irritates the vein walls, causing the vein to swell and then close. This process causes a gradual fading of the treated vessel over a period of several weeks to several months. Several treatments may be required to achieve optimum results. In some cases, as few as two or three treatments will do.