Bulging veins are usually harmless and often caused by exercise, heat, aging, genetics, or weight, making them more visible under the skin—especially on the legs and feet. In most cases, they’re a cosmetic concern, but painful veins with severe discoloration should be checked by a medical professional, as they can rarely signal conditions like blood clots.
These veins form when weakened vein valves allow blood to pool instead of flowing back to the heart. Smaller spider veins appear as flat red or blue web-like lines and are typically symptom-free, while larger varicose veins may bulge, ache, or swell due to poor circulation.
