When to worry about dark patches on skin with sun spots

Sun spots are areas of increased pigment that often appear on skin exposed to daylight, such as the face, hands, shoulders, chest, or arms. They can be tan to brown and may be flat with a clear edge. A patch can remain visible after the surrounding skin changes tone, so comparison with nearby skin is useful.

Look for a pattern that is stable and similar to your other spots. A patch that develops a new shade, becomes uneven at the edge, grows, crusts, or starts to itch or hurt does not fit a simple stable pattern and needs an in-person look. A clinician may examine it closely and decide whether testing is needed.

Take a clear photograph in even light and note when you first noticed the patch. Compare it with older photographs without repeatedly rubbing or picking the area. Use shade, protective clothing, and broad-spectrum sunscreen on exposed skin; this helps limit further darkening and protects the surrounding skin.

Avoid harsh bleaching products, scraping, or home acids on an unexplained patch. A dermatologist can distinguish sun-related pigment from inflammation, medication-related change, or another skin lesion and can discuss suitable treatment after examination.

Arrange a dermatology appointment if the patch is changing in size, shape, border, or colour, or if it repeatedly crusts, bleeds, feels tender, or fails to heal. Seek prompt medical care for rapid change, marked pain, spreading redness, pus, or fever. These features can signal infection or a lesion that needs timely assessment; they are not a measure of how common sun spots are.

Ask whether the patch has features of a sun spot, whether another diagnosis should be considered, and whether close examination or a sample is appropriate. You can also ask which sunscreen and pigment treatment suit your skin, how long improvement may take, and which changes should trigger a return visit.