Sclerotherapy is a minimally invasive procedure that treats varicose veins and spider veins. It involves injecting chemicals, known as sclerosing agents, into damaged veins.

In addition to diminishing the appearance of varicose or spider veins, sclerotherapy can also reduce pain or side effects caused by damaged veins.

Varicose veins can cause itching, pain, cramping, and discoloration. Spider veins are smaller and less severe than varicose veins. Varicose veins are more common in women than in men, although anyone can get them.

An estimated 20 percent of adults will be affected by varicose veins at some point in their lives. More than 324,000 sclerotherapy procedures were done in the United States in 2017.

The most common areas for varicose veins to develop are on your legs and feet.

The affected veins may be raised, discolored, or swollen, and some are deeper under the skin and can cause discomfort. Spider veins are smaller in size, closer to the surface of the skin, and can appear red, purple, or blue.

More rarely, sclerotherapy may be used to treat hemorrhoids. Sclerotherapy for the treatment of hemorrhoids is typically used when the hemorrhoids are smaller and external. It can also be used when the hemorrhoids bleed or when you can’t risk a surgical procedure such as a hemorrhoidectomy due to other health concerns.

Depending on the size of the damaged veins, sclerotherapy can be used to treat varicose and spider veins in the following areas:

  • thighs
  • calves
  • ankles
  • feet
  • face (frequently the sides of the nose)
  • anus

Depending on the severity of the condition, sclerotherapy treatment for venous problems can take anywhere from 15 minutes to an hour. If you’re getting treatment on your legs, your doctor may have you lie on your back with your legs elevated.

Depending on how far below your skin the damaged vein is, your doctor may use an ultrasound as part of the procedure.

The procedure begins with your doctor cleaning the skin around the targeted veins. With a fine needle, your doctor will inject the damaged vein with a sclerosing agent. Sclerosing agents typically used in sclerotherapy include:

  • polidocanol
  • sodium tetradecyl sulfate
  • hypertonic saline solutions

The liquid or foam solution causes the walls of the injected vein to seal shut, so blood is redirected to unaffected veins. Over time, your body absorbs the damaged vein, making it less visible and uncomfortable.

Based on the size of the treated vein or veins, you may need up to four treatments.

First, you’ll have a consultation with your healthcare provider. They’ll help you determine if this procedure is right for you.

In the few days before the procedure, your healthcare provider will usually recommend that you avoid certain medication, such as ibuprofen (Advil) and aspirin (Bufferin). This will help reduce your risk of bruising.

They may also recommend that you avoid applying lotion or shaving your legs before sclerotherapy to decrease irritation. You may also want to purchase and try on a compression stocking. You may be required to wear one for several days after the procedure.

You should let your healthcare provider know about any other medical issues you have before your procedure.

You may experience minor cramping, stinging, or burning in the injected vein during sclerotherapy. The procedure can also be painful, especially if the sclerosing agent leaks into surrounding tissues.

Common side effects of sclerotherapy include:

  • bruising
  • stinging
  • swelling
  • skin discoloration
  • discomfort
  • raised red areas that appear around the injection sites

All of these side effects should subside in a few days. Brown lines or spots can develop near the treatment area, as well. These normally disappear within three to six months, but in some cases this side effect lasts longer or may become permanent.

More serious side effects include:

  • allergic reaction to the sclerosing agent
  • ulceration of skin around the injection site
  • blood clot formation in the treated veins
  • inflammation that is usually mild can cause discomfort around the injection site

You should stay in touch with your healthcare provider after sclerotherapy treatment to help increase the efficacy of the procedure and manage any potential side effects.

According to the American Society for Aesthetic Plastic Surgery, the average cost of a single sclerotherapy procedure in 2017 was $369. The overall cost depends on the size and number of veins treated, as well as where you live.

Sclerotherapy is usually not covered by insurance if it’s done for cosmetic reasons. However, if you experience medical symptoms related to varicose veins, your insurance might cover the procedure.

There is little to no downtime associated with sclerotherapy. You’ll most likely be able to return to your everyday activities immediately.

In the first 24 hours after sclerotherapy, you may be advised to wear compression socks or stockings. You should only remove these to shower. After the first day, the stockings should be worn during the day and can be removed at night while sleeping.

You should use acetaminophen-based pain medicine such as Tylenol for any discomfort. Anti-inflammatory drugs such as aspirin and ibuprofen can affect your blood’s clotting process.

Avoid sunlight, hot baths, saunas, swimming pools, and the beach during the first two days after treatment.

You should also stay active to reduce the chance of blood clots. However, you should avoid aerobic exercises, such as running and weight lifting, for a couple of days. In some instances, you might be advised not to fly for several days as well.

Smaller varicose veins and spider veins respond best to sclerotherapy. You may be able to see improvement within a few weeks of treatment. For larger varicose veins, the visual improvement can take up to four months.

You may need several sessions to completely eliminate all the varicose or spider veins.

In a 2014 study, 83 percent of people who had sclerotherapy experienced a decrease in pain related to varicose veins.

It’s important to have realistic expectations about the effectiveness of sclerotherapy. Sclerotherapy doesn’t guarantee that there will be no visible traces or side effects of varicose or spider veins after the procedure.

Your healthcare provider can help you determine if you’re a good candidate for this procedure.