Dark circles under the eyes can appear for a number a reasons. If you have noticed a recent change, your doctor should check that there is no underlying problem. But only very few cases are caused by illnesses. The majority of dark circles are constitutional. This means that either your skin is very thin, so that tiny, damaged blood vessels leaking hemosiderin (iron pigment) show through; or the melanocytes in the skin here produce too much pigment. Another reason could be that your bone structure makes your eye area seem hollow and shadowy. Lack of sleep and smoking both aggravate dark circles, too.
There’s no miracle cure in a tube for constitutional dark circles. But Cernor XO emulsion gel can help improve their appearance, if they are mainly caused by ‘leaky’ blood vessels. Vitamin K in the formula helps strengthen ‘leaky’ blood vessels, while light-reflecting minerals help make dark under-eye circles appear less visible.