Cancer cells divide more quickly than healthy cells, and chemotherapy drugs effectively target those cells. Unfortunately, fast-growing cells that are healthy can be damaged too. There are many different chemotherapy drugs with the potential for many different side effects.
Symptoms & Signs. Dark circles under the eyes are a common complaint of both men and women, although they can occasionally be seen in children. As people age, the skin becomes thinner and collagen is lost, sometimes enhancing the appearance of blood vessels beneath the eyes and making the area appear darker.
Fatigue is the most common cause of dark circles under your eyes. Sometimes, what appear to be dark circles under your eyes may merely be shadows cast by puffy eyelids or hollows under your eyes that develop as a normal part of aging. Some of the most common causes of true under-eye circles are: Allergies.