Symptoms of Spider Veins The most common symptom is visible weblike appearance of red or blue vessels on the skin Why Should You Get Your Spider Veins Treated: The main reason behind treating spiders and thread veins is cosmetic; the only thing that you should keep in mind is that they might be a manifestation of vein reflux (valve failure) in the big veins of the skin. Stockings and medications are not accepted as treatments for ...