Typically, veins return blood from the rest of the body to the heart. To return blood to the heart, the veins in the legs must work against gravity. Weakened valves, also called incompetent valves, within the veins might cause varicose veins. The weakened valves let blood pool in the veins instead of traveling to the heart. When blood pools in the veins, the veins become larger, making them show under the skin.
Varicose veins are twisted, enlarged veins. Any vein that is close to the skin's surface (superficial) can become varicosed. Varicose veins most commonly affect the veins in the legs. That's because standing and walking increase the pressure in the veins of the lower body.
For many people, varicose veins and spider veins — a common, mild variation of varicose veins — are simply a cosmetic concern. For other people, varicose veins can cause aching pain and discomfort. Sometimes varicose veins lead to more-serious problems.
Treatment might involve self-care measures or procedures done by a health care provider to close or remove veins.
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Spider veins appear as thin, red lines or as weblike networks of blood vessels on the surface of the skin. Spider veins, a mild form of varicose veins, typically appear on the legs and feet.
Varicose veins might not cause pain. Signs of varicose veins include:
- Veins that are dark purple or blue
- Veins that appear twisted and bulging, often appearing like cords on the legs
When painful signs and symptoms of varicose veins occur, they might include:
- An achy or heavy feeling in the legs
- Burning, throbbing, muscle cramping and swelling in the lower legs
- Worsened pain after sitting or standing for a long time
- Itching around one or more of the veins
- Changes in skin color around a varicose vein
Spider veins are similar to varicose veins, but they're smaller. Spider veins are found closer to the skin's surface and are often red or blue.
Spider veins occur on the legs but can also be found on the face. They vary in size and often look like a spider's web.
When to see a doctor
If you're concerned about how your veins look and feel and self-care measures haven't helped, see your health care provider.
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Weak or damaged valves can lead to varicose veins. Arteries carry blood from the heart to the rest of the body. Veins return blood from the rest of the body to the heart. To return blood to the heart, the veins in the legs must work against gravity.
Muscle contractions in the lower legs act as pumps, and elastic vein walls help blood return to the heart. Tiny valves in the veins open as blood flows toward the heart, then close to stop blood from flowing backward. If these valves are weak or damaged, blood can flow backward and pool in the veins, causing the veins to stretch or twist.
The following can increase the risk of developing varicose veins:
- Age. Aging causes wear and tear on the valves in the veins that help control blood flow. Eventually, that wear causes the valves to allow some blood to flow back into the veins, where it collects.
- Sex. Women are more likely to develop the condition. Hormonal changes before a menstrual period or during pregnancy or menopause might be a factor because female hormones tend to relax vein walls. Hormone treatments, such as birth control pills, might increase the risk of varicose veins.
- Pregnancy. During pregnancy, the blood volume in the body increases. This change supports the growing baby but can also enlarge the veins in the legs.
- Family history. If other family members had varicose veins, there's a greater chance you will too.
- Obesity. Being overweight puts added pressure on veins.
- Standing or sitting for long periods of time. Movement helps blood flow.
Complications of varicose veins, although rare, can include:
- Ulcers. Painful ulcers can form on the skin near varicose veins, particularly near the ankles. A discolored spot on the skin usually begins before an ulcer forms. See your health care provider immediately if you think you've developed a leg ulcer.
- Blood clots. Occasionally, veins deep within the legs become enlarged and might cause leg pain and swelling. Seek medical attention for persistent leg pain or swelling because it can be a sign of a blood clot.
- Bleeding. Occasionally, veins close to the skin burst. Although this usually causes only minor bleeding, it requires medical attention.
Improving blood flow and muscle tone might reduce the risk of developing varicose veins. The same measures that treat the discomfort from varicose veins can help prevent them. Try the following:
- Avoiding high heels and tight hosiery
- Changing your sitting or standing position regularly
- Eating a high-fiber, low-salt diet
- Raising your legs when sitting or lying down
- Watching your weight