Varicose veins are generally not dangerous, but they can lead to complications if left untreated. In many cases, they are primarily a cosmetic concern, but some individuals may experience discomfort, pain and swelling. Over time, untreated varicose veins can result in more serious health issues, such as chronic venous insufficiency, where the veins struggle to circulate blood properly, leading to skin changes. Other potential complications include superficial thrombophlebitis (blood clots in superficial veins), deep vein thrombosis (DVT), which can be life-threatening if a clot travels to the lungs, and skin ulcers that can develop around the ankles.