Why Spider Veins Develop and What You Can Do to Treat Them

Written by Jennifer Robertson, MD, MSEd, NBHWC | Reviewed by Patricia Pinto-Garcia, MD, MPH Published on June 13, 2022

Key takeaways:

• Spider veins, also called telangiectasias, are swollen or damaged blood vessels. 
• Spider veins aren’t usually dangerous, but they can have a cosmetic impact. Sclerotherapy and other treatments can lessen the appearance of spider veins. 
• Regular exercise, maintaining a healthy weight, and avoiding smoking can lessen your risk of developing spider veins.

Albina Gavrilovic/iStock via Getty Images

Many people develop spider veins on their legs as they get older. Spider veins look like tiny red or purples lines, webs, or dots. Spider veins don’t tend to cause any symptoms but many people don’t like the way they look. 

If you’re concerned about spider veins, here’s everything you need to know about how to treat them and prevent more from forming. 

What are spider veins (telangiectasias)?

The proper medical term for spider veins is telangiectasias. Telangiectasias form when the tiny blood vessels in the top layers of the skin become swollen from blood pooling. Eventually, this pooling causes blood vessels to rip, which leads to more spider veins forming. Spider veins can also form anytime there’s damage to blood vessels, like from direct injuries.

Spider veins can develop anywhere on the body. They’re more likely to develop on your lower legs because gravity naturally causes blood to pool there. 

Telangiectasias became known as “spider veins” because they often form tiny clusters of blue, red, or purple lines. Together, these clusters look like a spider’s web. But telangiectasias can have other shapes, too. Sometimes, they look like straight lines or dots; other times, a cluster can look like a starburst. 

Can spider veins turn into varicose veins?

Spider veins can’t turn into varicose veins. Varicose veins develop when larger veins become dilated. These veins are in the deeper layers of the skin, while spider veins are in the uppermost layers. 

While the two aren’t directly connected, spider veins are sometimes described as a mild form of varicose veins.

You can develop both telangiectasias and varicose veins, but having telangiectasias does not mean you’ll definitely develop varicose veins. On the other hand, people who have varicose veins often develop spider veins, too. 

Why do some people develop spider veins (telangiectasias)?

The blood vessels in telangiectasias are tiny, so they’re fragile. It doesn’t take much for them to become dilated or damaged. 

Anything that increases pressure on these blood vessels can result in spider veins. Read about the most common culprits below.

Aging

As you get older, the walls of your tiny blood vessels become more prone to damage. And the stress of a lifetime of movement starts to catch up with your legs.That’s why people tend to develop spider veins on their legs as they get older. 

Genetics

Some people are more prone to developing spider veins, though the exact genetic cause still hasn’t been found. 

Research shows that people are more likely to develop telangiectasias if they have family members who develop them, too. In one study, 72% of people with spider veins had a first-degree relative who also had them. 

Medical conditions

Certain medical conditions — especially chronic venous insufficiency and chronic liver disease — increase your risk of developing spider veins. These medical conditions affect how well blood vessels are able to push blood back to the heart. When blood pools in veins, it leads to an increase in pressure inside the vein. And this pressure can damage the blood vessels, causing spider veins. 

Rosacea can also increase your risk of developing spider veins. Rosacea usually causes telangiectasia to form on the face.  

Pregnancy

Pregnancy increases the risk of developing spider veins in two ways:

1. Pregnancy causes a person to make more red blood cells, and the extra blood can make your blood vessels more dilated. 
2. A pregnant person has more estrogen and progesterone in their system, and these hormones cause blood vessels to dilate. 

Higher progesterone and estrogen exposure over a lifetime may also be why females are more likely to develop spider veins than males. 

Sun exposure

It’s no secret that excessive sun exposure isn’t great for your skin. But it turns out that it can also be damaging to your blood vessels. Studies show that people who have more exposure to the sun are more likely to develop spider veins.  

Medications

Some medications can increase the risk of developing telangiectasias. Chronic use of topical steroids can weaken skin, leaving blood vessels more vulnerable to damage. Hormonal birth control and hormone replacement therapy can also lead to spider veins, because the hormones in these medications cause blood vessels to dilate. 

What can I do to stop spider veins from developing?

There are some things that put you at risk for developing spider veins that you can’t control, like your age and genetics. But there are still things you can do to decrease the likelihood of telangiectasias appearing, including:

• Wear sunscreen. This will protect your skin and blood vessels from being damaged by ultraviolet rays. You can also protect your skin from the sun with things like hats and clothing.
• Stop smoking. Smoking increases your chances of developing blood vessel stiffening. When your blood vessels stiffen, they don’t work as well, which means blood is more likely to pool and cause spider veins. Fewer spider veins is just one more health benefit to quitting smoking.
• Exercise. Movement and exercise keeps muscles toned and active. When your muscles move, your blood vessels get squeezed, so blood doesn’t pool inside them. 
• Don’t stand or sit for too long. Sitting and standing for too long encourages blood to pool in your veins. This causes your vessels to dilate and form spider veins. It’s also a good idea not to cross your legs for too long, because it can trap blood in your vessels and make them dilate.
• Put your feet up. Elevating your feet and legs encourages blood flow. If you’re sitting, prop your feet up on a stool to keep blood from pooling in your veins.
• Wear compression socks. Compression socks deliver a constant squeeze to blood vessels in your legs, so blood can’t pool in them. 
• Maintain a healthy weight. Extra weight puts extra pressure on your legs. This makes it harder for your vessels to move blood against gravity, causing blood to pool in your veins.

How do you treat spider veins?

If you already have spider veins, you might be wondering what you can do about them. In general, telangiectasias do not go away on their own, but there are many treatments to get rid of them. Read more about these treatments below.

Sclerotherapy

Sclerotherapy is the most popular way to treat spider veins because it works well for most people. During sclerotherapy, a healthcare provider injects a medication into the damaged blood vessels so that they collapse and disappear. You may need more than one round of sclerotherapy to fully reduce the appearance of your spider veins.

Laser therapy

Laser therapy uses heat to treat spider veins. The medical-grade laser is guided over the areas of skin with spider veins, heating them up. This causes the spider veins to collapse and disappear.

Intense pulsed light therapy is similar to laser therapy, because it works by heating up the veins so that they collapse. But it uses high-intensity pulses of visible light.

Thermocoagulation

Thermocoagulation uses a tiny needle to deliver high-frequency energy that heats up and destroys spider veins. It’s sometimes used in combination with sclerotherapy to improve the appearance of spider veins.

The bottom line

Spider veins, or telangiectasias, form when tiny blood vessels in the skin become swollen or damaged. They’re commonly found on people’s lower legs. While spider veins aren’t usually bothersome or a cause for concern, they can have a significant cosmetic impact.

There are multiple treatment options for spider veins, including sclerotherapy. Exercise, wearing compression socks, elevating your feet, and quitting smoking are some of the many things that can help decrease the risk of developing telangiectasias.