Bulging veins aren’t always dangerous, but they can sometimes signal an underlying medical problem. They often become more visible due to factors like intense exercise, aging, hot weather, tight clothing, genetics, sun exposure, or excess weight. While harmless in many cases, any discoloration should be checked by a doctor.

Veins bulge when blood pools in weakened or damaged veins instead of flowing smoothly back to the heart, often resulting in varicose veins. These twisted, swollen veins usually appear on the legs but can also develop on the arms. Smoking, obesity, hormonal changes (especially during pregnancy), genetics, and long periods of standing or sitting are common contributors.

Treatment depends on severity and may include compression stockings, leg elevation, injection therapy, or surgery. If left untreated, varicose veins can lead to venous ulcers—painful, slow-healing wounds near the ankles caused by poor circulation—and even dangerous blood clots, which can result in deep vein thrombosis or pulmonary embolism.

While varicose veins can’t always be prevented, you can lower your risk by staying active, losing excess weight, quitting smoking, and wearing loose-fitting clothing, especially around the waist. Early attention to symptoms can help avoid serious complications and maintain better vein health.