Are Spider Veins Dangerous?

Thread veins or spider veins are extremely common and affect around 80% of adults at some point in their lives. They can affect both women and men and are a common side effect of pregnancy. But are spider veins dangerous?

This article will help explain what spider veins are and if they pose any serious threat to your health.

What are spider veins?

Spider veins are small blood vessels visible on the top layer of your skin. They appear most commonly on the legs but can also appear on the face, chest and even hands. Although very similar in appearance, spider veins on the face are different from those on the legs.

What causes spider veins?

Spider veins are often caused when the valves in the larger veins that allow blood to pump back towards the heart weaken or malfunction, allowing the blood to pool in smaller non-functional veins. This can occur for several reasons, the most common being pregnancy, standing or sitting for long periods, heredity, age and obesity.

Are any severe conditions associated with spider veins?

While spider veins don’t cause any health risks on their own, they can be an indicator of developing varicose veins. They may even mask hidden varicose veins which, when left untreated, can pose risks such as bleeding and blood clots.

Who is at risk of getting spider veins?

While over 80% of adults will suffer from spider veins at some point in their lives, some factors can increase a person’s risk of developing them, including:

  • Genetics – you are more likely to be at risk if other family members have thread veins.
  • Age – as the valves in your veins weaken over time, you are more likely to develop spider veins as you age.
  • Pregnancy – increases in blood flow and natural weight gain during pregnancy can put pressure on the leg veins and cause spider veins.
  • Sex – while spider veins can affect both women and men, they tend to affect women twice as much as men.
  • Hormones – hormone treatment and birth control can increase the risk of developing spider veins.
  • Being overweight – extra weight can put added pressure on the leg veins and increase your risk of developing spider veins.
  • History of blood clots or vein damage – can cause your veins to become damaged and weaken and increase your risk.
  • Sitting or standing for long periods – staying in one position for long periods causes the veins in your legs to work harder and become damaged, increasing your risk.

Spider veins alongside other conditions

People who have spider veins and a health condition that affects the circulatory system are at a higher risk of developing vein-related complications. For example, a person with spider veins and diabetes may be more likely to have a deep vein thrombosis (DVT).

Diagnosis and treatment

Many generalist surgeons offer spider vein treatments. However, only a specialist venous consultant surgeon has the training, knowledge and skills to:

  • Effectively diagnose any underlying conditions
  • Devise the most suitable treatment plan for long-term results
  • Treat the spider veins and any underlying conditions.


The first step in spider vein treatment is a proper assessment of the leg veins and a diagnosis of any underlying conditions. This process involves:

  • A duplex scan – a non-invasive procedure that uses ultrasound to examine the structure of the leg veins and indicates the speed of blood flow within them.
  • A consultation – in which the consultant will ask you about your medical history and your treatment aims.
  • A physical examination of your legs.

Allowing your consultant to diagnose any underlying vein issues, including varicose veins, leads to more straightforward treatment. If left untreated, varicose veins can cause pain and other more severe symptoms.


Once your consultant has arrived at a diagnosis, she or he will recommend a treatment package for you.

Spider veins

If you have spider veins without any underlying conditions, your choice of treatment is straightforward. There are many products and procedures that claim to treat thread veins such as creams, laser or light therapies and electrolysis. However, microsclerotherapy is the only technique that produces reliable long-term results for surface and deeper veins.

Varicose veins

If you have varicose veins in addition to spider veins, you may be offered a wide range of non-surgical and surgical treatment options, including:

  • Non-surgical walk-in-walk-out procedures – such as radiofrequency ablation (RFA), endovenous laser ablation (EVLA) and ultrasound-guided foam sclerotherapy (UGFS).
  • Surgery – highly invasive procedures such as ligation and stripping, which the National Institute of Clinical Excellence (NICE) says should only be considered if endovenous ablation and foam sclerotherapy are deemed unsuitable.

The best procedure will depend on your diagnosis, medical history and preference. In most cases, any underlying varicose vein treatment can also be completed alongside the treatment for spider veins.

Compare varicose vein treatment options

Our approach to diagnosing and treating spider veins

Premier Veins offers a free no-obligation mini-consultation so that you can ask any questions that you have about treatment, meet the team that would treat you and make an informed decision about choosing us.

Full consultation

If you decide to pursue treatment with Premier Veins, one of our world-leading specialist venous consultant surgeons will see you for a full consultation which will include:

  • Taking a detailed medical history
  • Duplex scan
  • Physical examination of your legs
  • Agreeing your fixed-price treatment plan with you.

Spider vein treatment prices


In most cases, we are able to complete the first round of treatment on the same day as your consultation.

12-month guarantee

All varicose vein treatments come with a 12-month guarantee. If you develop new or recurring veins within 12 months of receiving treatment with us, we will re-treat at no cost to you.

Book your FREE mini-consultation today!

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