Sclerotherapy is the most common procedure used to treat spider veins and varicose veins. During treatment, a liquid chemical called a sclerosing solution is injected into the vein, causing the vein walls to seal shut. After time, the vein breaks down, turns to scar tissue and then disappears.

Varicose veins are identified by their enlarged, gnarled appearance. They may be red or blue and often bulge beyond the surface of the skin. Spider veins are like varicose veins in that they are enlarged and red- or blue-colored; however, these veins are thinner and appear closer to the skin's surface. Both varicose and spider veins may ache or throb, worsening when you stand or sit for long periods of time.

What is sclerotherapy?

A non-surgical procedure, sclerotherapy is the most common treatment for both spider veins and reticular (varicose) veins.

Our nurse practitioners inject a solution into the vein that causes the vein walls to swell, stick together and seal shut. This stops the flow of blood, and the vein turns into scar tissue. The same vein may need to be treated more than once. A number of vessels may be injected during a treatment session. Most patients experience a 50-90% improvement. Sclerotherapy does not require anesthesia, and can be done in the doctor's office.

What happens during sclerotherapy?

Your plastic surgeon will thoroughly examine the veins you are concerned about, taking notes of your symptoms. Venous reflux disease, the abnormal recirculation of blood, causes symptoms similar to those related to varicose and spider veins, so it's important to see a doctor regarding the condition.

Once your diagnosis is confirmed, you may be recommended for sclerotherapy. The procedure is performed in your plastic surgeon's office and lasts 15-30 minutes. First, the skin is cleansed with antiseptic, and then the sclerosing solution is injected into the vein. This solution is often composed of detergents, osmotic agents and chemical irritants. An injection is needed for every inch of vein (5-40 injections per session), and 2 or more sessions are usually required at 4- to 6-week intervals.

If the vein cannot be seen on the skin's surface, ultrasound may be used to help guide the insertion of the needle. Ultrasound-guided sclerotherapy is also commonly performed in a plastic surgeon's office.

What happens after sclerotherapy?

It is important to remember to limit your activities for a few days following sclerotherapy, though walking is encouraged to help speed the recovery process. You may experience cramping, redness and bruising, symptoms that are treatable with the application of tight-fitting support hose for the first 72 hours or more following treatment. Please contact your surgeon or health professional if your symptoms persist or worsen.

Our physicians welcome your questions concerning sclerotherapy. Please call us if you have a suspicious or unwanted vein or would like to learn more about treatment options for varicose or spider veins.

Frequently asked questions

  • A: The injection uses a fine needle that causes a barely noticeable pinprick feeling. Some people experience a slight to moderate burning feeling immediately after the injection, but this disappears after a few seconds.

  • A: To improve the blood circulation in the deep veins, it is essential to walk after the treatment. A compression stocking is worn to reduce the risk of bruising and swelling or other complications. This may help seal the treated vessels, keep the blood from collecting under the skin, and reduce the development of dark spots. It may also reduce the number of treatments necessary, as well as the possibility of recurrence.

    Regular exercise, weight control and the use of support stockings (if practical) are recommended between treatments and after treatments.

  • A: There are some possible side effects. They include:

    • Stinging or pain at the injection sites, swelling of the ankles or feet, or muscle cramps. This usually occurs when hypertonic saline solution is used. Hive-like reactions usually go away within 10-15 minutes after injection.
    • Red, raised areas at the sites of injection. These are similar to hives and should disappear within a day or so.
    • Brown lines or spots on the skin at the sites of treated blood vessels. Darkened areas may result when blood escapes from treated veins. These dark areas occur more often in patients who have larger veins treated or those patients that tan easily. In most cases, they disappear within a year.
    • Development of groups of fine red blood vessels near the sites of injection of larger vessels. About a third of patients develop groups of vessels especially on the thighs. Most disappear by themselves. Some need additional injection treatments or laser therapy. A few may last.
    • Small, painful ulcers at treatment sites either immediately or within a few days of injection. These occur when some of the solution escapes into the surrounding skin or enters a small artery at the treatment site, and can be successfully treated, but it is necessary to inform the vascular surgeon immediately.
    • Temporary bruises. Bruises usually occur after laser treatments and are probably related to the thinness of blood vessel walls. They usually disappear in a few weeks. 
    • Allergic reactions to sclerosing solutions. Inform your vascular surgeon immediately if you think you have an allergy to this solution. This is very unusual, but when it occurs, it is treated with medications such as aspirin, compression, antibiotics or heat.
    • Lumps in injected vessels. This is coagulated or “trapped” blood and is not dangerous. The surgeon may drain the blood from these areas a few weeks after injection, if needed.
    • Burning with discoloration of the skin.
  • A: Large veins may recur even after surgical procedures. Spider veins may also recur. It may seem that a previously injected vessel has recurred when in fact, a new spider vein has appeared in the same area.