HyperpigmentationThe changes most often cause physiological by dye, which is called melanin. Skin pigment melanin is the most important factor for the resulting skin colour. It is synthesized by dendritic cells in the basal epidermal layer - melanocytes. Hyperpigmentation may be diffuse or focal, when areas are affected such as the face and the back of the hands.
Hyperpigmentation can be caused by sun damage, inflammation, and skin injuries, including those related to acne vulgaris. Moreover, people with darker skin tones are more prone to hyperpigmentation, especially with excess sun exposure.