Does hyperpigmentation cause dark patches on skin?

Hyperpigmentation means an area of skin looks darker because pigment production or distribution has changed. The colour may be brown, grey or nearly black, and the area can be flat or uneven in tone. It may follow acne, eczema, an injury, irritation, inflammation or sun exposure.

Dark patches can also reflect other skin conditions or, less often, a wider health problem. A clinician considers when the patch appeared, whether it is changing, its texture and its location rather than relying on colour alone.

Use broad-spectrum sun protection on exposed areas, avoid picking or scrubbing, and stop products that burn or repeatedly irritate the patch. Treating active inflammation can help prevent further pigment change. Do not apply bleaching products or prescription creams without professional guidance.

A dermatologist may recommend observation, a topical treatment, a procedure or management of the underlying trigger. Improvement often takes time because pigment-containing skin cells must gradually be replaced.

Arrange an assessment for a new, spreading, itchy, painful, bleeding or raised dark patch, or one that changes in shape or texture. Seek prompt advice if many areas darken quickly or darkening occurs with other unexplained symptoms.

What is the likely trigger? Could irritation or inflammation be maintaining the colour change? Which treatment is safe for my skin tone, and how should I protect the area from sunlight?