Varicose veins are enlarged, distorted veins just under the skin, most commonly found in the legs. Normally, muscle contractions in the legs help to push blood through veins, and one-way valves in the veins prevent the blood from flowing backward. Varicose veins develop when the valves fail to close properly, causing a backflow of blood; this increases pressure in the veins and makes them swell.
Varicose veins are often caused by increased pressure from swelling of the abdomen during pregnancy or in obesity, or from prolonged standing. Rarely, they are due to the veins being abnormally stretchy or having too few valves. In addition to their appearance, varicose veins may cause symptoms, such as aching, burning, or throbbing in the legs; swollen feet and ankles; and leg cramps. The skin over a varicose vein may also become dry and itchy, may bleed easily, and may become ulcerated. Varicose veins usually do not require any treatment other than compression stockings and measures to prevent the condition from getting worse, such as weight loss, exercise, and avoiding prolonged standing.
If necessary, varicose veins may be treated by sealing off the affected veins or by removing them completely.