Hyperpigmentation is the darkening of an area caused by increased melanin. It can result in flat, darkened patches of skin that can vary in size and shape. People with darken skin tones are more prone to pigmentation, especially with excess sun exposure, but it can affect people with all skin tones.
There are many types of hyperpigmentation, but the most common are:
Post-inflammatory hyperpigmentation can occur when a skin injury or trauma heals. For example, acne break outs may be left behind after pimples heal. This can leave a flat area of discolouration behind. This can also be caused by procedures such as chemical peels, laser and abrasive microdermabrasion.