“What causes spider veins on the legs?”

There are several causes
- standing or sitting for prolonged periods
- pregnancy
- obesity
- hereditary
- previous blood clots in legs that result in valve damage

Spider veins are tiny veins that appear just below the skin surface, usually in a fan-like pattern. They develop from increased pressure in the small capillaries that bring oxygen and nutrients to the skin. They can come about due to a problem with the underlying veins that transmits pressure into these surface veins, or from a weakness in the vein wall which causes them to stretch.

The best way to treat these veins (assuming underlying vein issues have been taken care of) is by injection sclerotherapy. This is where a tiny needle is used to inject a medication which irritates the inside of the vein and causes it to close up. This should only be done by a vein specialist, as there are a wide variety of sclerosants that can be used, and picking the right one is important for the best results.

The most common cause her spider veins is what is known as deep venous insufficiency secondary to the valves inside of the veins not functioning properly. This can be evaluated with an outpatient ultrasound and an accredited vascular lab. You need to be an almost upright position for the test to be properly done.