Spider veins are blood vessels located just beneath the skin surface that grow larger and appear red or blue when they weaken and become clogged. They most often appear in “sunburst” patterns on the face and legs, but also can affect other areas of the body.

Spider veins appear in both sexes, but are more common in women. More than 40 percent of women will suffer from abnormal leg veins by the time they are in their 50s, according to the U.S. Department of Health and Human Services. Spider veins are usually considered medically harmless, although they may cause a dull, aching sensation after prolonged standing. In rare cases, they may be associated with more serious health conditions such as liver or venous disease.

A number of different therapies are available to treat spider veins. These include sclerotherapy, a procedure in which a dermatologic surgeon injects a solution into the spider vein. The vein closes up or collapses, turns into scar tissue and is absorbed by the body over a period of months.