Sclerotherapy involves a doctor injecting a solution into blood vessels or lymph vessels that causes them to shrink. Generally, it is a safe and effective treatment that can help with varicose veins or spider veins.

Sclerotherapy is a nonsurgical procedure. Doctors may also use it to treat blood and lymph vessel disorders that cause vessels to form incorrectly.

The solution is called a sclerosant, and it irritates the targeted vessel, causing it to swell. This swelling cuts off the flow of blood or lymphatic fluid, and the vessel shrinks.

In this article, we look at the uses of sclerotherapy, what to expect from it, and what recovery entails.

Sclerotherapy is a medical procedure used to treat varicose veins. The procedure involves injecting the affected vein with a solution which causes the vein to fade and become a scar. Overtime the varicose vein will fade from view. This procedure has a moderate chance of success.Share on Pinterest
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Sclerotherapy is a first-line treatment for varicose veins, which can be a sign of chronic venous insufficiency.

Varicose veins refer to veins, usually in the legs, that swell and bulge due to poorly functioning vein valves. As a result, blood pools in the veins. This issue may be painful and itchy and cause skin discoloration.

Sclerotherapy shrinks varicose veins until they disappear, and blood reroutes to healthier veins.

Find home remedies for varicose veins here.

Doctors may also use sclerotherapy to treat other health issues, including:

  • Malformed lymph vessels: These are abnormal vessels in the lymphatic system. Sclerotherapy creates scarring in the malformed vessels, causing them to collapse.
  • Hemorrhoids: Doctors may use sclerotherapy to shrink grade 1 or 2 hemorrhoids. These form when blood vessels surrounding the rectum swell and become irritated, causing pain and making bowel movements uncomfortable.
  • Hydroceles: A hydrocele is a collection of fluid around a testicle. Doctors may use sclerotherapy to treat hydroceles, particularly when surgery is unsuitable.

People may consider sclerotherapy to treat varicose veins or spider veins. Some may have the procedure for cosmetic reasons. A doctor can help a person decide if sclerotherapy is necessary or suitable.

People may want to consider other approaches first. For example, people can usually treat hemorrhoids with strategies such as lifestyle changes, eating more fiber, and not straining when having a bowel movement.

People with varicose veins or spider veins might consider sclerotherapy if the veins are too twisted for other treatments to work or if they have uncomfortable symptoms, such as:

  • itching
  • aching
  • burning
  • swelling
  • night cramps
  • the legs feeling very heavy or tired

Learn about painful varicose veins here.

A doctor assesses the problematic veins or lymph vessels before recommending this approach.

Sclerotherapy is usually an outpatient procedure that lasts 30–45 minutes. Anyone having it on the legs may need to wear shorts. People should also arrange for transportation home afterward.

During the procedure, a doctor uses a fine needle to inject the sclerotherapy solution into the varicose or spider vein. They may use ultrasounds to guide them. There may be a mild burning sensation or cramping for a few minutes during the treatment of larger varicose veins.

Alternately, the doctor may administer an anesthetic and insert a catheter into the affected blood vessel, then use a solution of 90% alcohol to block the vein.

In most cases, a person needs follow-up treatments to collapse a vein fully. Treating several varicose veins, in particular, may require multiple appointments.

To prepare for sclerotherapy, people should follow any instructions from their doctor. This may involve avoiding certain medications, such as aspirin or blood thinners, or using lotions on the area of treatment.

After the treatment, it is likewise important to follow the doctor’s advice. People may need to wear compression stockings to help with recovery and prevent further varicose veins from forming.

Also, some people have some bruising or marks at the site of the injection.

Spider veins usually respond to the treatment in 3–6 weeks, and larger veins usually respond in 3–4 months. If the treatment is successful, the veins will disappear. If not, the doctor may recommend repeated treatments.

A person may need to have a follow-up appointment with their doctor for a physical examination and possibly imaging or blood tests to check the effects of the sclerotherapy.

According to 2016 research into the effects of sclerotherapy treatment for abnormal blood vessel development, sclerotherapy is successful in around 75–90% of cases.

If the treatment is successful, spider or varicose veins will not reform. However, new veins may appear, and if they become problematic, a person may need repeated treatments.

If trained, qualified healthcare professionals do sclerotherapy correctly, it is a safe and effective treatment.

However, having existing medical conditions, not following medical advice, or taking medications that conflict with the treatment may significantly increase the risk of complications.

Also, sclerotherapy may not be not suitable for people who are pregnant, breastfeeding, or confined to bedrest. After giving birth, people must wait 3 months before having sclerotherapy.

Possible risks and complications of sclerotherapy include:

  • an infection, which requires treatment with antibiotics in under 1 in 1,000 cases
  • a skin injury that may result in a small, permanent scar
  • severe inflammation
  • an allergic reaction to the injected solution
  • a blood clot

Also, if tiny air bubbles from foam sclerotherapy get into the bloodstream, it may cause chest tightness, a dry cough, dizziness, and nausea.

Deep vein blood clots

In rare cases, a blood clot forms in a deep vein due to sclerotherapy. This can become life-threatening if the clot travels to another area, such as the lungs.

To reduce this risk, a doctor only injects a small amount of solution at a time, and they encourage the person to move their legs to support proper blood flow.

Anyone who experiences any chest pain, difficulty breathing, or dizziness after sclerotherapy should receive emergency medical care.

Research suggests that sclerotherapy removes problematic veins in 75–90% of cases, but this typically requires multiple treatments. When sclerotherapy does not work, people may require other treatments, such as surgery.

Sclerotherapy may not be effective for everyone. Under 10% of people may not have any response to the treatment, regardless of the size of the veins in question.

If sclerotherapy is ineffective or unsuitable, a doctor may try injecting a different sclerosing solution or recommend another approach, such as cutaneous laser therapy.

Insurance coverage for sclerotherapy depends on whether the insurer considers the procedure to be medically necessary.

When spider veins are a cosmetic concern only, insurance companies might not cover the procedure. Also, some insurers may require people to try other procedures first, such as cryotherapy to freeze the veins.

Regardless of the health issue that needs treating, a doctor may have to show that other treatments have failed and that sclerotherapy is likely the safest and most effective approach.

Not all malformed veins require treatment. When there are no other symptoms, a doctor may simply monitor over time to see if they get worse or start causing symptoms.

Lifestyle changes may help prevent the issue from worsening and help relieve symptoms. These may include:

  • maintaining a healthy weight, to relieve excess pressure on the veins and improve blood flow
  • avoiding long periods of sitting or standing, or sitting with the legs elevated above the heart
  • stay physically active to help promote blood flow, after discussing a suitable exercise plan with a healthcare professional

Alternative procedures may include:

  • endovenous ablation, which uses lasers to close off the vein
  • surgically removing smaller veins that are closer to the surface of the skin
  • surgically tying up and removing larger veins

To treat varicose veins, a doctor may also suggest compression therapy, such as wearing compression stockings, or medications, such as diosmiplex.

Learn more about compression stockings for varicose veins here.

Sclerotherapy is usually a minor, noninvasive procedure to treat issues such as varicose veins or hemorrhoids. It involves a doctor inject a solution that causes the problematic veins to shrink and collapse. This may require repeated treatments.

The outlook is good, as the procedure is typically safe and effective.

It is important to discuss the benefits and risks of sclerotherapy with a doctor, and possible coverage with an insurer, before making a decision.