How common are dark patches on skin in post-inflammatory hyperpigmentation?

Post-inflammatory hyperpigmentation is extra pigment left behind after inflammation or injury settles. It can follow acne, eczema, a rash, a burn, an insect bite, or a procedure. The patch usually appears where the earlier irritation occurred and may be tan, brown, grey, or deeper in tone depending on skin colour and the depth of pigment. It is usually a colour change rather than an active infection, but the original trigger still matters.

Treat the active cause gently and avoid scrubbing, picking, or using products that sting. Protect affected skin from sunlight because exposure can deepen the contrast and slow fading. A dermatologist may suggest a targeted topical treatment after identifying the trigger and your skin type. Do not apply strong lightening products without guidance, particularly to recently irritated skin.

Book an assessment if the dark area keeps expanding, develops a raised or scaly surface, bleeds, or does not match a previous rash or injury. Get help for ongoing itch, pain, swelling, or oozing, which may signal continuing inflammation or another condition. Review is also sensible when pigmentation follows a procedure and the skin is worsening rather than settling.

Ask what likely caused the inflammation, whether it is still active, and which ingredients are suitable for your skin. Clarify how to protect the area, when fading should be reviewed, and which warning changes would need prompt reassessment.