Red marks after acne
In short
Flat pink, red or purplish marks where spots have healed are post-inflammatory erythema, or PIE. They come from small blood vessels left behind by inflammation rather than from pigment, so they can fade with time. Vascular light and laser treatments have been studied for marks that persist, while pigment-targeting products address brown marks instead.
Written by the Seoul Facial Redness editorial team and medically reviewed by a Korean Board-Certified Dermatologist (AAD International Fellow · ASLMS member). Last reviewed: .
What is post-inflammatory erythema?
Inflamed acne spots bring extra blood flow and new small vessels to heal the skin. When the spot settles, some of that vascular change can stay behind as a flat red mark. Dermatologists introduced the term post-inflammatory erythema in 2013 to describe this pink-to-red discolouration after inflammatory acne, separate from pigment marks and scars.[1]
PIE tends to stand out on lighter and medium skin tones, while darker skin more often shows brown marks after acne. The two can sit side by side.
Is it PIE, PIH or an acne scar?
| Mark | Colour | Press test | Surface |
|---|---|---|---|
| Post-inflammatory erythema (PIE) | Pink, red or purplish | Usually fades for a moment under a pressed clear glass | Flat |
| Post-inflammatory hyperpigmentation (PIH) | Light to dark brown | Stays the same colour | Flat |
| Atrophic scar | Skin-coloured, shadowed | No change | A dip or pit |
| Active spot | Red | May lighten a little | Raised, often tender |
The press test is a quick home check, not a diagnosis. Many people have all three kinds of mark at once, and the mix decides the treatment plan.
Do red acne marks fade on their own?
Many do, gradually. But PIE can be slow: one treatment study enrolled only people whose marks had lasted more than six months.[2] Three habits help marks fade and stop new ones forming: controlling active acne, not squeezing or picking, and daily sun protection.
Which treatments help red acne marks?
| Option | What studies found | Plan used in studies |
|---|---|---|
| Intense pulsed light (IPL) | 49 of 60 patients (81.7%) had complete or partial clearance of red and brown marks | 3–7 sessions, 4–6 weeks apart |
| Fractional microneedling radiofrequency | Significant reduction in redness in a Seoul chart review, without severe side effects | 2 sessions, 4 weeks apart |
| Pulsed dye laser | Improved PIE in the case reports that named the condition | Varies |
| Time, acne control and sunscreen | Lets existing marks fade and prevents new ones | Ongoing |
The IPL figures come from a retrospective study of 60 Chinese patients treated with sequential filters at 560–640 nm. Seven of them (11.7%) had an acne relapse during six months of follow-up, so ongoing acne control still matters after treatment for marks.[2]
Fractional microneedling radiofrequency delivers heat through fine needles. In a Seoul National University chart review, 25 patients who had two sessions four weeks apart showed significant improvement in redness without severe side effects; the review also followed 27 patients treated with antibiotics or creams. Skin biopsies after treatment showed fewer vascular and inflammatory markers.[3]
The pulsed dye laser was the treatment described in the paper that named PIE, but that report was based on individual cases.[1] Other vascular devices, such as the 1064 nm Nd:YAG laser, are also used for red marks; ask what evidence the clinic is relying on for the device it suggests.
Can I treat acne marks while I still have breakouts?
Usually the first step is to calm active acne, because every new inflamed spot can leave a new mark. Some plans run both at once: acne medicine for the spots and light or laser for older marks. If you are on oral acne medicine, tell the clinic before any procedure.
Can I treat red acne marks during a short trip to Seoul?
Courses in the studies above ran every four to six weeks, which suits people who visit Seoul regularly or can continue treatment at home. A single visit is still useful: it confirms which marks are PIE, PIH or scars and gives you a plan. Redness after IPL or radiofrequency is covered in redness after procedures.
Are red acne marks permanent?
Usually not. PIE is a vascular change rather than lost tissue. Some marks persist for many months, and that is the point at which light or laser treatment is worth discussing.
Is PIE the same as rosacea?
No. PIE sits exactly where acne spots were. Rosacea redness spreads across the cheeks, nose and chin and flares with triggers such as heat and alcohol.
Will brightening serums fade red acne marks?
Brightening products are designed for pigment, so they address brown marks (PIH). For red marks, sun protection and time come first, and vascular light and laser treatments are the options studied for marks that persist.
References
Bibliographic records retrieved from PubMed (U.S. National Library of Medicine).
- Bae-Harboe YS, Graber EM. Easy as PIE (Postinflammatory Erythema). J Clin Aesthet Dermatol. 2013;6(9):46-7. PubMed: 24062874
- Wu X, Wang X, Wu X, et al. Intense Pulsed Light Therapy Improves Acne-Induced Post-inflammatory Erythema and Hyperpigmentation: A Retrospective Study in Chinese Patients. Dermatol Ther (Heidelb). 2022;12(5):1147-1156. PubMed: 35415801
- Min S, Park SY, Yoon JY, Kwon HH, Suh DH. Fractional Microneedling Radiofrequency Treatment for Acne-related Post-inflammatory Erythema. Acta Derm Venereol. 2016;96(1):87-91. PubMed: 26059315