Pigmentation is the coloring of a person's skin. When a person is healthy, his or her skin will appear normal in color. In the case of illness or injury, the person's skin may change color, becoming darker (hyperpigmentation) or lighter (hypopigmentation).

Hyperpigmentation

Hyperpigmentation is caused by an increase in melanin, the substance in the body that is responsible for color (pigment). Certain conditions, such as pregnancy or Addison's disease (decreased function of the adrenal gland), may cause a greater production of melanin and hyperpigmentation. Exposure to sunlight is a major cause of hyperpigmentaion, and will darken already hyperpigmented areas.

Hyperpigmentation can also be caused by various drugs, including some antibiotics, antiarrhythmics, and antimalarial medication.

Melasma

An example of hyperpigmentation is melasma (also known as chloasma). This condition is characterized by tan or brown patches, most commonly on the face. Melasma can occur in pregnant women and is often called the "mask of pregnancy;" however, men can also develop this condition. Melasma frequently goes away after pregnancy. It can also be treated with certain prescription creams (such as hydroquinone).

If you have melasma, try to limit your exposure to sunlight. Use a strong sunscreen (SPF 15 or higher) at all times, because sunlight will worsen your condition. Sunblocks containing zinc oxide or titanium dioxide are best; although, sunscreens with Parsol 1789 (avobenzone) will also provide good protection.

Consult with your doctor before treating the condition yourself.

Hypopigmentation

Hypopigmentation is the result of a reduction in melanin production. Examples of hypopigmentation include:

Vitiligo: Vitiligo causes smooth, white patches on the skin. In some people, these patches can appear all over the body. It is an autoimmune disorder in which the pigment-producing cells are damaged. There is no cure for vitiligo, but there are several treatments, including cosmetic cover-ups, corticosteroid creams, or light treatments.
Albinism: Albinism is an inherited disorder caused by the absence of an enzyme that produces melanin. This results in a complete lack of pigmentation in skin, hair, or eyes. Albinos have an abnormal gene that restricts the body from producing melanin. There is no cure for albinism. People with albinism should use a sunscreen at all times because they are much more likely to get sun damage and skin cancer. This disorder can occur in any race, but is most common among whites.
Pigmentation loss as a result of skin damage: If you've had a skin infection, blisters, burns or other trauma to your skin, you may have a loss of pigmentation in the affected area. The good news with this type of pigment loss is that it's frequently not permanent, but it may take a long time to repigment. Cosmetics can be used to cover the area, while the body regenerates the pigment.

Reviewed by doctors at The Cleveland Clinic Department of Dermatology.

WebMD Medical Reference provided in collaboration with the Cleveland Clinic