Spider veins are small varicose veins that can occur in any part of the body. They are caused by numerous factors, including pregnancy, obesity, poor circulation, and sun damage.They are usually blue or red in color and most people get them on their legs. Spider veins are not dangerous, but they can be unsightly and cause discomfort. If you have spider veins, there are several treatment options available to you. Here are five of the best known remedies: