There are a number of possible complications that can occur with vein treatments even when the greatest of care is taken.

Pigmentation is the appearance of brown marks on the skin located over or near the treated veins. This is a common consequence of treatment, particularly when treating spider vein clusters with injection sclerotherapy. Pigmented areas are composed of haemosiderin (a form of iron) that can become trapped in the skin. In most patients the pigmentation gradually fades, disappearing completely within 3-12 months although faint pigmentation lasting greater than 12 months has been reported in 5% of cases. Close attention to wearing of the compression stocking will minimise pigmentation. It is advisable to stop iron supplements two weeks before your treatment. Recently, topical laser therapy has proved promising in reducing areas of pigmentation.

Matting is the development of extremely fine networks of spider veins likely to occur on the outer and inner thighs. Matting usually resolves spontaneously though some will resolve with further injection treatment. Some may persist despite further treatment. Matting is more common in people with extensive surface veins and in overweight people with poor muscle tone. Matting can also follow the surgical removal of varicose veins. 

Swelling of the leg or ankle occurs occasionally and will settle with time. It is due to inflammation of the skin. Wearing the compression stocking, elevating the leg when sitting and regular walking will help. However, it may take several weeks to settle. 

Numbness of the skin is rare and temporary but can last up to three months. It is usually located down the inner aspect of the thigh or back of the calf. It is due to irritation of nerves that lie close to a treated vein. Numbness can be expected for a few hours with EVLA procedures as local anaesthetic is used to numb the area around the vein prior to treatment. 

Migraine sufferers may experience visual disturbances lasting a few minutes and can occur in patients treated with injection sclerotherapy. This may be followed by the onset of a headache. Taking a mild analgesic such as Panadol or Panadeine or anti-migraine medication can provide relief. Should you suffer with migraines then you may choose to bring a friend to assist with driving home. Migraine has not been reported with EVLA alone.

Ulcers of the skin are rare and usually appear as small, painful sores within two weeks of injection sclerotherapy treatment. They heal slowly and leave a scar, which can be excised if unsightly. They occur due to sclerosant passing from the injected veins into the small associated skin arterioles, or may be due to spasm in these small arterioles. Ulcers are more common in people who smoke cigarettes or who have certain associated skin conditions. Ulcers are not seen with EVLA. 

Allergic reactions to either the sclerosant used or to the local anaesthetic are rare but may be serious and life threatening. Some reactions require immediate treatment. Should you feel any abnormal sensations during treatment such as generalised itchiness, nausea or shortness of breath, don’t hesitate to tell the doctor who will then provide the appropriate treatment. 

Deep Vein Thrombosis is a clot in the deep venous system – not in the treated veins. This potentially serious problem is extremely rare if the compression stocking is worn as directed and regular daily walking is maintained. The approximate risk is less than 1 in 5000 patients for sclerotherapy and even less in EVLA cases. This is compared to 1 in 200 people with surgical stripping. If your relative risk of DVT is considered increased then prophylactic treatment such as injections of Clexane will be advised. Deep vein thrombosis may lead to clots in the lung (pulmonary embolism), which can be a life threatening condition requiring hospitalisation. Approximately 1 in 4 people with a DVT have clots in the lungs and of these approximately 1 in 20 is fatal. It is advisable to avoid long distance travel (greater than 5 hours duration) for at least 4 weeks following the treatment of varicose veins. Should you need to travel within 4 weeks of your last treatment please contact the Vein & Laser Centre doctors. 

Symptoms of deep vein thrombosis and pulmonary embolism include a painful swollen calf or leg unrelieved by walking, unusual shortness of breath, cough with or without blood stained sputum and stabbing chest pain. Should you experience any of the above symptoms please contact the doctor immediately. 

Intra-arterial injection is an extremely rare complication that can result in significant muscle and skin damage. This now rarely occurs due to the use of ultrasound guidance of the needle, which allows for a more accurate placement during the injection procedure. 


Pregnancy and breastfeeding – sclerotherapy is best avoided when pregnant or breastfeeding. This is advised even though there is no current documented evidence to suggest that sclerotherapy is unsafe during pregnancy or breastfeeding. Vein treatments during pregnancy are not as effective, often producing poor results. It is recommended that sclerotherapy should be avoided if pregnancy is contemplated within the treatment course. Veins that appear during pregnancy should be treated before the next pregnancy to avoid deterioration with subsequent pregnancies. 

Oral contraception and hormone replacement therapy – both oestrogen and progestogen have been implicated in increasing the risk of thrombosis whether you have a vein treatment or not. Taking the low dose contraceptive pill or HRT increases the risk of deep vein thrombosis 3 fold as compared to those not taking these products. Total correction of this increased risk requires ceasing hormone treatment for a minimum of 4 weeks. The increased risk seems to lessen the longer you have been on the medication. There is no current evidence that during sclerotherapy or EVLA treatment the taking of low dose oral contraceptive pill or HRT actually increases the risk of thrombosis above the already existing risk before treatment. The relative merits of ceasing or continuing hormone therapy prior to sclerotherapy and EVLA will be discussed.

There are no reported long-term side effects from the use of sclerosants or laser treatment.