White spots that won't tan: what should you know?

When nearby skin darkens, an area with reduced pigment can look more obvious. This may follow a previous rash, irritation or injury; some conditions affect pigment production directly. Fine scale, a sharp border, itching, or spots that join together can provide useful clues. The colour alone does not establish a diagnosis.

Sunburn can make the contrast stronger and can injure both the pale area and surrounding skin. A clinician will consider the spot's history, distribution and surface rather than judging it by tanning behaviour.

Use broad-spectrum sunscreen on exposed skin, wear protective clothing, and avoid tanning beds. Moisturise if the area is dry, but do not scrub, peel or apply bleaching mixtures. Photograph the spots in consistent lighting and record whether they spread, change texture or follow an earlier irritation.

If the appearance bothers you, discuss camouflage or a targeted treatment only after the cause is known. Treating the underlying condition is usually more useful than trying to darken the patch.

Arrange a skin assessment when new pale spots continue to appear, enlarge, become scaly or itchy, or affect the face, hands or genital area. Seek prompt advice if pigment loss is accompanied by eye symptoms, significant inflammation, blisters, pain or a rapidly changing mole-like mark.

Ask whether the surface suggests inflammation or infection, whether any examination under a special light is useful, how to protect the area outdoors, and which cosmetic products are safe while the diagnosis is being clarified.