What should you know about a large dark spot on your back?

Darkening can follow a bite, rash, spot, wound, or other inflammation; this is called post-inflammatory hyperpigmentation. Sun spots are another possibility, while melasma usually forms broader, fairly even areas of pigment. Tinea versicolor can create lighter or darker patches with fine scale, often across the trunk.

A photograph cannot reliably identify the cause. Note the spot’s outline, colour, surface, texture, and whether it is changing. A clinician may inspect it closely and decide whether further evaluation is needed.

Use broad-spectrum sun protection on exposed skin and avoid deliberate tanning, because ultraviolet exposure can deepen many pigment changes. Do not scrub, bleach, or apply strong lightening products without advice; irritation can make pigmentation more noticeable.

Treatment follows the cause. Options may include a chemical peel, skin brightening treatment, or picosecond laser treatment, but these are not interchangeable and can worsen pigment if used on the wrong diagnosis or skin type. Diagnosis comes before cosmetic treatment.

Book a dermatology assessment for a new or enlarging mark, an irregular border, several colours, bleeding, crusting, persistent itching, or tenderness. Seek prompt review if the spot changes noticeably over a short time or develops an open sore. A stable, evenly coloured patch may be less urgent, but still deserves assessment if it is new or unexplained.

Ask which features suggest post-inflammatory hyperpigmentation, melasma, sun spots, tinea versicolor, or another diagnosis. Discuss whether examination alone is enough, which sun-protection routine fits your skin, and whether a peel, brightening treatment, or laser is suitable after the cause is clear.