Sclerotherapy is the injection of a chemical solution into unwanted blood vessels. Sclerotherapy irritates the vessel walls, making them stick together. This leads to fibrosis of the vessel, which becomes unable to carry blood and less visible under the skin. Doctors describe a vein that has been obliterated in this way as ‘sclerosed’.
Sclerotherapy is most commonly used for the treatment of unwanted, visible spider veins and superficial (surface) varicose veins. Spider veins (thread veins) are tiny red or blue veins that can appear anywhere on the body but occur most commonly on the legs. Varicose veins are generally larger veins that can be raised above the skin’s surface. Varicose veins can sometimes cause aching legs and swelling of the ankles. They can also be associated with burning, stinging, throbbing, restless legs and leg cramps.
Not all varicose veins are suitable for sclerotherapy — if the varicose veins are large or if the valves in the veins are very leaky, surgery may be a better option than sclerotherapy. Your doctor may suggest an ultrasound to see whether your veins are suitable for sclerotherapy.
These blood vessel abnormalities commonly occur in families, which suggests they may be an inherited condition. They affect women more often than men, most commonly appearing in pregnancy. It is also believed that prolonged standing may be a factor in the development of these abnormalities, along with previous injury or severe bruising. Obesity, being tall and using oestrogens (as in the oral contraceptive pill and hormone replacement therapy) are all considered minor risk factors for varicose veins.
With sclerotherapy, the doctor will use very fine needles to inject the sclerosing solution into the blood vessels. In some cases the doctor will use ultrasound to guide the needle.
Various types of sclerosing solutions can be injected into the veins — studies have so far shown no difference between sclerosing solutions in terms of their effect on varicose veins.
Multiple vessels can be injected during one treatment session. The injections usually cause minimal discomfort although some people might experience a slight to moderate burning sensation immediately after the injection.
Your veins may require a number of repeat injections over a period of weeks or months to ensure they are fully sclerosed and fade from view. A compression stocking is usually applied following treatment for at least a week.
While most patients can expect at least a 75 per cent improvement in their treated veins, total clearance may not occur.
Following treatment there are often raised, red areas at the injection sites. These usually resolve within the hour. People may also notice bruising and occasionally the sclerosed vein will appear more pronounced after treatment; however, these effects are short-lived.
Temporary aching in the legs can also occur and this can be helped by walking and by taking paracetamol if necessary. Other possible side effects of sclerotherapy include:
Long-term side effects of sclerotherapy are unusual. Veins that have been adequately treated with sclerotherapy will not recur; however, new vessels may appear over time. Support stockings, weight control and exercise are thought to be helpful in preventing the development of these vessel abnormalities, in particular varicose veins.
Last Reviewed: 19 February 2010