Patchy skin color refers to areas of irregular skin coloring. Mottling or mottled skin refers specifically to blood vessel changes in the skin which cause a patchy appearance.
Irregular or patchy discoloration of the skin can be caused by:
The following can increase or decrease melanin production:
Exposure to sun or ultraviolet (UV) light, especially after taking a medicine called psoralens, may increase pigmentation. Increased pigment production is called hyperpigmentation.
Decreased pigment production is called hypopigmentation.
Skin color changes can be a single disorder, or they may result from other medical conditions or disorders.
How much skin pigmentation you have can determine, to some extent, which skin diseases you may be more likely to develop. For example, lighter-skinned people are more sensitive to sun exposure and damage, which raises the risk for skin cancers. However, too much sun exposure can lead to skin cancers even in darker-skinned people. See:
Generally, pigment changes are cosmetic and do not affect physical health. However, psychological stress can occur because of pigment changes. Some pigment changes may be a sign that you are at risk for other medical disorders.
Normal skin color may return on its own in some cases.
You may use lotions that bleach or lighten the skin, such as hydroquinone, to reduce hyperpigmented skin or to even the skin tone where hypopigmented areas are large or very noticeable.
Selsun blue or tolnaftate (Tinactin) lotion can help treat tinea versicolor. Apply as directed to the affected area daily until the lesions disappear. Unfortunately, tinea versicolor often returns no matter what type of treatment is used.
You may use cosmetics or skin dyes to disguise skin color changes. Makeup can help hide mottled skin, but will not cure the problem.
Avoid excessive sun exposure and use sunblock. Hypopigmented skin sunburns easily, and hyperpigmented skin may get even darker. In darker-skinned people, skin damage may cause permanent hyperpigmentation.
Contact your doctor if you have any persistent skin coloring changes without a known cause.
Also call if you you notice a new mole or other growth, or if an existing one has changed color, size, or appearance.
The doctor will carefully examine the skin and ask questions about your medical history and symptoms, such as:
Tests that may be done include:
Dyschromia; Mottling