Post-Inflammatory Hyperpigmentation (PIH): Treatment Guide

Post-inflammatory hyperpigmentation (PIH) is the flat brown or tan mark left behind after the skin has been inflamed — most familiarly after a pimple, but also after irritation, ingrown hairs or a procedure. It is crucial to understand that PIH is a pigment problem, not a scar: there is no change in the skin's contour, just colour.

That distinction is good news, because pigment fades. PIH usually clears on its own over weeks to months, and the right care — above all sun protection — speeds it up. The key is not to mistake it for a scar and over-treat it.

When skin is inflamed, the inflammation signals pigment cells (melanocytes) to ramp up melanin production. That excess melanin is deposited in the area as a flat dark mark. In deeper skin tones, pigment cells are more reactive, so PIH is both more common and more persistent — and pigment can drop deeper into the skin, where it fades more slowly.

Because it is driven by inflammation, the most effective prevention is to limit inflammation in the first place — controlling acne, not picking, and avoiding harsh treatments.

Two look-alikes cause confusion. Acne scars are changes in contour (depressions or raised tissue) that do not fade on their own. PIE (post-inflammatory erythema) is the red or pink version of PIH — lingering blood-vessel redness rather than brown pigment, more common in lighter skin. Each is treated differently, so identifying which you have matters.

The simple test: PIH is flat and brown and fades; a scar dents or raises and persists; PIE is flat and red. When unsure, a doctor can tell them apart quickly.

Time and sun protection do most of the work. Daily broad-spectrum sunscreen is non-negotiable, because UV deepens and prolongs PIH. Supportive topicals that calm pigment production speed fading. For stubborn marks, gentle peels or cautious pigment-aware laser can help — used carefully, since over-treatment can ironically cause more PIH.

Crucially, any active source of inflammation (such as ongoing acne) must be controlled first, or new marks keep appearing faster than old ones fade.

See a doctor if your marks are widespread, slow to fade, or you are not sure whether they are PIH, PIE or scars. An assessment confirms the diagnosis and, importantly, addresses any ongoing inflammation (like active acne) that keeps generating new marks.

At DrPlus in Johor Bahru, PIH is treated gently and patiently, with the cause controlled first.