In some patients, an annoying consequence of Sclerotherapy is dark staining of the skin where the spider veins have been treated. Fortunately, severe cases are uncommon and invariably, even with severe cases, the pigmentation fades with time. The patients that are of greatest risk of developing pigmentation are those who are from Asia or those who have Asian parents. There are also patterns of veins that are more likely to result in pigmentation after treatment.
The reasons for this are not clear. It doesn’t make medical sense that people with darker skin are more prone to pigmentation because the pigmentation is due to Ferritin (which an iron breakdown product of blood) and not Melanin (which is elevated in people with darker skin). The time frame for the fading can be up to 2 years but fortunately with most patients is usually much less. There is nothing that can be done to speed up the process. There are however several techniques that can be used during the initial spider vein treatment that will minimise the risk of pigmentation in those who are at higher risk.
