What is Sclerotherapy

Dr Zara Kassam

What is Sclerotherapy?

Sclerotherapy is a non-surgical procedure that helps to treats varicose and spider veins by injecting chemicals, known as sclerosing agents directly into the affected vein. The damaged vein is reabsorbed and eventually fades, leaving a clear area of skin. It is sometimes called microsclerotherapy, but this is usually reserved for the spider or thread veins.


How does it work?

The first stage of the procedure involves cleaning the skin around the targeted veins; then with a fine needle, injecting the chemical solution directly into it.

The FDA has approved two solutions to date, these are:

  • Sodium tetradecyl sulfate and
  • Polidocanol (Asclera).

The chemical solution causes the walls of the injected vein to shut, thereby redirecting the blood to unaffected veins. Over time, our body will reabsorb the damaged vein, making it less visible


How long Does it take?

Sclerotherapy can take anywhere from 15-60 minutes depending on the size of the veins being treated.


Is Sclerotherapy painful?

Sclerotherapy in not a painful, however as it requires an injection, some discomfort may be felt at the site of the injection.


What is the recovery time?

There is no downtown; people who have had the procedure are strongly advised to walk and remain active after the treatment. They are also required to wear compression socks for up to 3 weeks to reduce the risk of blood clots.


What are the side effects?  

Sclerotherapy is a relatively safe procedure which has been used since the 1930’s with few complications. However, some mild side effects may occur at the site of the injection these include:

  • Bruising
  • Raised red areas
  • Small skin sores
  • Itchy skin around the injection site

These side effects usually go away within a few days to 2 weeks.

More serious complications that may arise as a result of Sclerotherapy include:

  • Inflammation – Usually mild but may cause swelling
  • Blood clots –A lump of clotted blood may form in a treated vein that may require drainage.
  • Skin ulceration – If the solution goes into the surrounding tissues it can cause a small ulcer of the skin. This may take several weeks and could leave a scar.
  • Deep venous thrombosis (DVT) – If the solution passes into the deep veins there is a risk of thrombosis.
  • Lumps – Larger veins that have been injected may become lumpy and hard and may require several months to dissolve and fade.
  • Brown lines or spots – these may appear at the vein site. they usually disappear within 3-6  months, but may persist.
  • Neovascularisation – the development of new, tiny blood vessels around the site of sclerotherapy treatment. These tiny veins can appear days or weeks after the procedure, but should fade within three to twelve months without further treatment.

Should any of the following side effects occur, contact your doctor immediately. These include:

  • Red and inflammation skin within five inches of the groin
  • Sudden leg swelling
  • The development of small ulcers or wounds at the injection site.

Allergic reactions to the fluid that’s injected may occur at the time of the injection and are rarely serious. Your doctor may test the agents on a small area before applying them to a larger area.

If you have any concerns or questions following this procedure, contact your doctor.

Following the treatment avoid aspirin, ibuprofen, or other anti-inflammatory drugs for at least 48 hours.

It is also best to avoid:

  • Hot baths
  • Whirlpools or saunas
  • Sun exposure


Is it suitable for everyone?

Cosmetic sclerotherapy is not advised during pregnancy or breast feeding. On the NHS you are not eligible for the treatment  if you are pregnant.

It should also be avoided if you:

  • are allergic to any of the ingredients
  • are taking the contraceptive pill
  • have a local skin infection
  • have a serious heart condition including heart disease or weak valves which require surgery
  • have an uncontrolled disease e.g. diabetes
  • are unable to walk.


How much does it cost?

The average cost for sclerotherapy varies by the size and number of veins being treated. Treatments can range anywhere from £300 to more than £2000 depending on how many injections are needed and how many sessions are required.


Who can do this procedure?

It should only be performed by qualified medical professionals.

Is it effective?

Sclerotherapy is an effective technique to eliminate or collapse veins. Studies have indicated that as many as 50%-75% of injected veins may be eliminated with each session.

In general, spider veins respond quite well and disappear in three to 6 weeks. Larger veins can take longer – up to 3-4 months. They should not reappear, but new veins may appear at the same rate as before and you may need to return for further injections.

There are other options available including laser and IPL treatments as well. Very large varicose veins may require surgery.


[1] https://www.circulationfoundation.org.uk/help-advice/veins/varicose-veins-injection-treatment-or-sclerotherapy

[2] https://emedicine.medscape.com/article/1271091-treatment

[3] https://www.bassclerotherapy.com/articles/sclerotherapy-faqs/

[4] https://www.ncbi.nlm.nih.gov/pubmed/22825857

[5] https://www.webmd.com/skin-problems-and-treatments/cosmetic-procedures-sclerotherapy#1