Are Spider Veins Bad? Why They Form & When To See a Doctor

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Table of Contents

  • Symptoms of spider veins
  • How do spider veins form?
  • Are spider veins bad?
  • When to see a doctor about spider veins

Spider veins are small blue, red, or purple veins on your legs, feet, and face. They form when small blood vessels near the surface of your skin called capillaries become damaged and swollen.1 

The medical term for spider veins is telangiectasias, but they’re sometimes also called thread veins, sunburst veins, stellate veins, venus flares, and hyphen webs. Spider veins are very common. Some studies suggest that almost all adults will get spider veins at some point, but they’re most common between ages 30 and 50. Women are four times more likely to have them.3 

Symptoms of spider veins

Spider veins look like thin, squiggly lines resembling tree branches or sunbursts. They usually appear on your legs or face and are visible just under the skin.4 Spider veins can occur in a small area or spread across your leg, but the size doesn’t affect symptoms.5

Spider veins rarely cause symptoms, but you can experience:6

  • Burning
  • Pain

Blood flows in different directions through your body. Arteries carry oxygen-rich blood from your heart to your body, and veins carry low-oxygen blood back to your heart. Capillaries are tiny veins that carry blood between arteries and veins.7 Spider veins are swollen capillaries and can look different depending on where the irregularities start.8

Spider veins originating from the artery are flat and usually pink or red, and those with a vein origin are usually slightly raised and blue or purple.9

How do spider veins form?

Spider veins happen because of irregularities in a network of vessels under your skin called a vascular plexus. It’s not exactly clear why you get spider veins, though there are a few theories.10 

Varicose vein disease

Some experts think that spider veins are a mild or early type of varicose vein disease and happen because of chronic venous insufficiency, known as CVI.11 

Blood flows back to your heart in veins with one-way valves. When these valves don’t work properly, blood can flow toward your feet and pool up, causing your veins to enlarge. Pressure builds inside your veins, and you end up with large, stretched, swollen veins called varicose veins.12

Spider veins aren’t exactly the same because they’re capillaries and don’t have valves.13 However, experts think CVI can also lead to spider veins.14 The theory is that as the varicose veins become inflamed and weak, blood pools in the surface veins and cuts off the oxygen supply. New vessels form, and the existing veins branch out and bulge, creating a spider-like appearance. However, studies show that only 23% of people with CVI also had spider veins.15

Hormonal changes

Spider veins might also be linked to hormonal changes, which could be why they’re more common in women. You might get spider veins during pregnancy, at certain times of your period cycle, or during menopause. Some hormonal medications like birth control pills might also cause spider veins.16 

Other risk factors

Certain lifestyle and hereditary factors can increase your risk of getting spider veins, including:17

  • Sitting, standing, or walking for long periods
  • Obesity
  • Injuries
  • Smoking
  • Family history of blood clots
  • Getting older
  • Sunlight

Extra weight, a lack of movement, and prolonged standing or walking put additional pressure on your veins and make them work harder to pump blood, which can cause them to swell. You might also see these pop up during pregnancy because of the extra weight and pressure on and the extra blood in your veins.18

Are spider veins bad?

Spider veins are mostly a cosmetic problem. They don’t cause any medical issues or interfere with your blood flow or vessel function. The appearance of spider veins often bothers many people, which can cause emotional distress or self-esteem problems.19

While spider veins rarely cause any problems, they can sometimes cause physical symptoms when you also have varicose veins. You might have pain, throbbing, and itching, especially if you sit or stand for a long time.20

In most cases, varicose veins don’t cause problems either but can lead to tired and achy legs and rare cases of:21

  • Skin sores
  • Bleeding
  • Blood clots just under the skin
  • Blood clots in deeper veins 

When to see a doctor about spider veins

Sometimes spider veins can get smaller or completely go away on their own, especially after pregnancy.22 In other cases, you might have spider veins and not even notice. 

With some self-care and lifestyle adjustments, you can manage your symptoms at home or prevent spider veins from developing. You can:23

  • Exercise regularly to help your leg muscles that help pump blood back to your heart
  • Get up and move after 30 minutes of sitting
  • Sit down after 30 minutes of standing
  • Put your feet up when you’re sitting to help blood flow back to your heart
  • Lose weight
  • Wear gradient compression stockings

Spider veins generally don’t need treatment, but you should see your doctor if:24

  • You’re worried about their appearance
  • They bother you and affect your self-esteem
  • Suddenly change and become very painful, hot, red, or swollen 
  • The skin on your ankle or foot changes color

In most cases, your doctor will treat your spider veins for cosmetic reasons. The most common technique is sclerotherapy, where they inject a chemical into your vein, causing it to swell, scar, and then seal shut.25

Eventually, your body breaks down these veins, absorbs them, and grows new ones. The treatment doesn’t prevent future spider or varicose veins, so you might need several treatments to see improvements.26If you think your veins need help, talk to your vein specialist. Learn more about spider veins and varicose veins from My Vein Treatment.


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  2. Office on Women’s Health: “ Varicose veins and spider veins.”
  3. StatPearls: “ Spider Veins.”
  4. Johns Hopkins Medicine: “ Varicose Veins.”
  5. Medscape: “ Varicose Veins and Spider Veins.”
  6. StatPearls: “ Spider Veins.”
  7. Johns Hopkins Medicine: “ Overview of the Vascular System.”
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  11. StatPearls: “ Spider Veins.”
  12. Johns Hopkins Medicine: “ Chronic Venous Insufficiency.”
  13. Cleveland Clinic: “ Blood Vessels.
  14. StatPearls: “ Spider Veins.”
  15. Office on Women’s Health: “ Varicose veins and spider veins.”
  16. Office on Women’s Health: “ Varicose veins and spider veins.”
  17. American Academy of Dermatology Association: “ Leg Veins: Why They Appear and How Dermatologists Treat Them.”
  18. Office on Women’s Health: “ Varicose veins and spider veins.”
  19. StatPearls: “ Spider Veins.”
  20. StatPearls: “ Spider Veins.”
  21. Office on Women’s Health: “ Varicose veins and spider veins.”
  22. Office on Women’s Health: “ Varicose veins and spider veins.”
  23. Office on Women’s Health: “ Varicose veins and spider veins.”
  24. Office on Women’s Health: “ Varicose veins and spider veins.”
  25. Office on Women’s Health: “ Varicose veins and spider veins.”
  26. StatPearls: “ Spider Veins.”

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