Risks

Sclerotherapy results in few serious complications.

Temporary side effects

Some side effects that may occur at the site of the injection include:

• Bruising
• Raised red areas
• Small skin sores
• Darkened skin in the form of lines or spots
• Multiple tiny red blood vessels

These side effects usually go away within a few days to several weeks. Some side effects can take months or even years to disappear completely.

Side effects that may require treatment

Other complications are less common but may require treatment. These include:

• Inflammation. This is usually mild but may cause swelling, warmth and discomfort around the injection site. Your doctor may suggest an over-the-counter pain reliever such as aspirin or ibuprofen (Advil, Motrin IB, others) to reduce the inflammation.

• Blood clot. A lump of clotted blood may form in a treated vein that may require drainage. Rarely, a blood clot may travel to a deeper vein in your leg (deep vein thrombosis).

  Deep vein thrombosis carries a risk of pulmonary embolism (a very rare complication of sclerotherapy), an emergency situation where the clot travels from your leg to your lungs and blocks a vital artery. Seek immediate medical care if you experience difficulty breathing, chest pain or dizziness, or you cough up blood.

• Air bubbles. Tiny air bubbles may rise in your bloodstream. These don't always cause symptoms, but if they do, symptoms include visual disturbances, headaches, fainting and nausea. These symptoms generally go away, but call your doctor if you experience problems with limb movement or sensation after the procedure.
• Allergic reaction. It's possible that you may have an allergic reaction to the solution used for treatment, but this is uncommon.