What is Sclerotherapy?

For people struggling with unsightly or painful varicose veins or spider veins, a treatment called sclerotherapy can be very valuable. Often thought of as the “treatment of choice” for smaller varicose veins, sclerotherapy involves injecting a solution directly into the vein—the solution will cause the vein to scar, and force blood to reroute through other veins.

What is sclerotherapy, and how might it benefit you? Let’s find out.

Sclerotherapy Purpose

In many cases, sclerotherapy is done for purely cosmetic purposes. It helps improve the appearance of varicose and spider veins that can be bothersome for many people. It can also help with related symptoms including:

  • Aching
  • Swelling
  • Burning
  • Night cramps

Doctors advise waiting on sclerotherapy if you’re pregnant or breastfeeding.

Minor Side Effects

Sclerotherapy is a relatively safe procedure with limited complications. Certain temporary side effects might take place near the site of the injection such as:

  • Bruising
  • Skin sores
  • Raised red areas
  • Dark skin, forming in lines or spots
  • Multiple tiny red blood vessels

In most cases, these side effects will go away in a few days or weeks. Some may last months or even years until they fully disappear.

There are also a few less common side effects that may require treatment:

  • Inflammation: Generally mild, but can lead to swelling, warmth and discomfort near injection site. Aspirin may help.
  • Blood clot: A clotted lump may form inside the treated vein and may require drainage. In some rare cases, the clot will move down to a deeper vein in the leg and cause a condition called deep vein thrombosis. This condition carries the risk of a pulmonary embolism, a condition where the clot travels into the lungs and blocks an artery.
  • Air bubbles: Tiny air bubbles in the bloodstream may appear, and may or may not cause symptoms. Symptoms can include headaches, fainting, nausea and visual disturbances.
  • Allergic reaction: It’s rare, but some people have an allergic reaction to the solution used for treatment.


A few basic exams or processes will take place in advance of sclerotherapy:

  • Physical exam: Your doctor will check the veins to be treated and the presence of any underlying blood vessel disease.
  • Medical history review: Your doctor will ask about any recent conditions (especially related to heart conditions or blood clots), medications or supplements, allergies and any previous treatment you’ve had for varicose veins. Ultrasound: The doctor may request imaging to help with the process.

For 24 hours prior to the procedure, don’t shave your legs or apply any lotion. Wear loose and comfortable clothing to your appointment—if weather permits, some people wear shorts to leave the legs exposed.

The Procedure

The sclerotherapy procedure is done at your doctor’s office and does not require anesthesia. In most cases, it will take under an hour to complete. Steps of the procedure include:

  • You’ll be asked to lie on your back with your legs elevated
  • Your doctor will cleanse the area with alcohol
  • A fine needle will slowly be inserted into the affected vein, and will push a solution into the vein
  • The solution, typically a liquid, will begin irritating the lining of the vein, causing it to swell shut and block the flow of blood
  • The doctor will remove the needle and apply compression or massage to help keep blood out and disperse the solution

Some people experience minor stinging or cramps at the needle insertion point—if this pain becomes severe, tell your doctor.

Post-Op and Results

After the procedure, you should be able to get up and walk around right away. Do this regularly, as movement is important to prevent blood clots. You’ll be given instructions on compression stockings or bandages, which are typically worn for about two weeks. In most cases, you can return to normal activities right away, though it’s often a good idea to have someone available to drive you home.

Your doctor will likely advise you to avoid strenuous activity for a couple weeks and avoid sun exposure to the treated areas during that time.

For small varicose or spider veins, definitive results will usually show up in three to six weeks. Larger veins may take three to four months, and in both cases, multiple treatments might be required. Your doctor will likely schedule a follow-up visit for about a month after the procedure. Sclerotherapy has an overall success rate of between 60 and 80 percent for eliminating spider and varicose veins.

If you’re looking to get rid of spider or varicose veins speak to your doctor about whether sclerotherapy might be a good option for you.


“Sclerotherapy for Varicose and Spider Veins.” WebMD.

“Sclerotherapy.” The Mayo Clinic.

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