In general, the procedure is fairly painless. When the Doctor is treating you, you may feel some stinging for a few minutes. However perception of pain is a personal issue and varies from one person to another. Following the treatment, you may have some pain along the treated veins for a few days. Aching can persist for up to two weeks and this shows that the procedure is working. Walking and Paracetamol can help with pain relief. The stocking may rub into the skin causing a blister behind the knee. Make sure you adjust the stockings and pull it up otherwise you may get a blister.



Following treatment you may notice bruising which will settle down after a few days. It is important NOT to use creams such as Lasonil or Hirudoid before or after the treatment.

Darkening of the veins

In some patients the treated veins become darker immediately after treatment. It is a good sign and indicates the success of the treatment. Once darkened, the veins will disappear over 3 weeks with improvements continuing for up to 3 months.

Staining of the skin

A small group of patients may notice brown discoloration of the skin along the treated vein. This is due to deposition of iron pigments (haemosiderin) in the skin and depends on the amount of iron stored in your body. It is important to stop Iron supplements before your treatment. If this discolouration occurs it may take up to 1 year to resolve but in rare cases it may take many years to resolve. Any underlying veins which may contribute to the pigmentation will be identified and treated.


Small tiny capillaries may develop on the skin surface following the treatment. They usually resolve within 4 to 6 months but may take years to resolve. This is one of the reasons why it is advisable to stop the Oral Contraceptive Pill or Hormone Replacement Therapy before your treatment and use compression stockings after the treatment. It is also important to stop Vitamin E supplements and Fish Oil and avoid applying creams containing Vitamin E to your legs during your treatment.

Trapped Blood

With the treatment of larger veins, blood may get trapped within the treated veins. You may feel tiny tender lumps along the treated vein or you may feel the whole length of the treated vein as a palpable long line. This is NOT a complication. If it occurs, the doctor may decide to release the trapped blood at the time of your next appointment. This happens by simply pricking the vein and letting the trapped blood out. If it is not released, trapped blood may take a few weeks but will be eventually absorbed. We normally release the trapped blood if it’s causing pain, discomfort or discoloration.


This is inflammation of the treated superficial veins and presents as tender, red and swollen lumps. It is commonly confused with an infection. Infection is NOT an associated risk of sclerotherapy and the red hot lumps are almost always due to phlebitis. This complication can be avoided especially if compression stockings are used appropriately after the treatment. It resolves completely with adequate compression and anti-inflammatory medications that the doctor may wish to prescribe. Excessive exercise during the treatment period, lack of compression, loose stockings, excessive walking and hormones such as HRT are the common risk factors for phlebitis.

Deep Vein Thrombosis (DVT)

These are blood clots in the deep veins (not the treated veins). DVT may be dangerous and can travel to the lungs resulting in a life threatening condition called pulmonary embolism. This may be related to genetic tendencies towards clotting (thrombophilia). If you have a past history or family history of clotting, please let the doctor know to arrange appropriate testing before treatment. Using compression stockings and walking immediately after the treatment and on a daily basis is essential in reducing the risk. We also advise against long distance travel (air, car, coach) or extensive periods of immobility within 4 weeks before or after UGS and CDS. To prevent clotting please stop any hormonal medications (Oral Contraceptive Pill or Hormone Replacement Therapy) 4 weeks before the treatment.

Ulcers and tissue loss

Rarely, small arterioles adjacent to treated veins go into spasm resulting in formation of a small ulcer. This ulcer will heal after 2-3 months but may leave a scar. An intra-arterial injection (injection of the sclerosant in the arteries) can cause a much bigger ulcer and tissue (fat, muscle, etc) loss and the associated complications of such loss. Not all intra-arterial injections cause an ulcer but they usually cause some tissue loss either of the fat or the adjacent muscles and nerves. This is a major complication of sclerotherapy but the risk is less with ultrasound guided procedures.

Migraine and Neurological symptoms

Patients who normally suffer from migraines might experience the same symptoms shortly after the treatment. Those with a hole in the heart (Patent Foramen Ovale) may experience neurological symptoms such as flashing lights, headaches or other symptoms. These are transient (lasting up to 2-3 hours) and have no long term consequences. There are documented cases of stroke after Sclerotherapy in patients with a PFO. If you have a history of heart problems, holes in the heart or previous strokes, please let the doctor know.

Allergic reaction

Very rarely a patient may be allergic to the solution used. The risk of allergic reaction might consist of simple hives and itchiness or even anaphylaxis (severe allergic reaction) and death. If you have a history of allergies please let the doctor know. If you are allergic to one solution we can use a different solution to treat your veins.


In very rare cases, an area of skin may develop numbness. This is due to inflammation of the nerves close to the treated
veins. It usually resolves 3-6 months after the treatment but may take up to one year and rarely even longer to resolve. This is an extremely rare complication in this practice.


After the treatment of large veins, swelling of the ankles may follow. It settles with the use of compression, elevation of the leg and walking but it may last for up to 3 months. Pregnancy and breast feeding: There have been no studies to show if this treatment has any effects on pregnancy or the baby. In general we do not recommend this type of treatment during pregnancy or breast feeding.

It is your responsibility not to fall pregnant during treatment.

For more information on the Effects of sclerotherapy, please contact us on (02) 9386 0211 or click here