Varicose veins are gnarled, swollen veins that can be seen just under the surface of the skin, usually in the legs or feet. Veins move blood to the heart and have one-way valves that prevent blood from flowing backward. When those valves become weakened for long periods, blood can back up and pool in an area, causing the veins to become ropey and swollen. Varicose veins are common and usually don't cause medical problems, but do sometimes cause pain, blood clots, skin ulcers, or other problems. If you have varicose veins and have any of these symptoms, seek a medication evaluation.
Varicose veins are usually not cause for concern. However, on occasion they can cause pain and medical problems. People who have cardiovascular disease and varicose veins, along with other risk factors like hypertension, may be prone to skin breakdown and skin infections from varicose veins. Varicose veins may also be a warning sign of other circulatory problems.
Varicose veins are different from deep vein thrombosis (DVT), but severe varicose veins may increase the likelihood of developing DVT, a condition in which blood clots form deep in the veins. When this occurs, the blood clots can break loose and move through the bloodstream, lodging in the lungs and blocking blood flow.