Post-Inflammatory Hyperpigmentation: What It Is
Quick facts
- Definition
- Darkening of the skin that appears after inflammation or injury, due to increased melanin at the site.
- Types
- Epidermal (brown, sharper edges) and dermal (gray or blue-gray, more persistent).
- Who is at higher risk
- Higher phototypes, generally IV to VI, and skin exposed to the sun during healing.
- Triggers in HOF
- Hematomas, irritation, infection, surface procedures, microneedling and lasers.
- Relevance in HOF
- It is one of the most common aesthetic complications in pigmented skin and calls for prevention and guidance.
Post-inflammatory hyperpigmentation is the darkening of the skin that appears after inflammation or injury, such as acne, a burn, a cut or a procedure. Inflammation stimulates melanocytes to produce more melanin and sometimes leaves pigment in the dermis, creating a mark at the site. In HOF, it answers a frequent concern: a mark after an aesthetic procedure, more common in skin of a higher phototype.
Why does the mark appear?
Mediators released during inflammation stimulate the production and transfer of melanin. When the pigment stays in the epidermis, the mark is brown and tends to fade faster. When inflammation damages the basal layer, some of the pigment drops into the dermis and is captured by immune cells, and the mark turns gray or blue-gray, with slower progress.
| Type | Usual look | Usual course |
|---|---|---|
| Epidermal | Brown, sharper edges | Fades over weeks to months |
| Dermal | Gray or blue-gray, diffuse edges | May persist for many months |
| Mixed | Combines both looks | Variable |
Which procedures can cause it?
Any injury that inflames the skin can leave a mark. In HOF routine, the triggers most often recalled are:
- Hematomas and ecchymoses after injection, especially in thin, pigmented skin.
- Irritation from antiseptics, dressings or excessive manipulation.
- Infection and prolonged inflammatory processes.
- Surface procedures, such as peels, microneedling and lasers.
- Sun exposure during recovery.
How do you tell it apart from other color changes?
- Hematoma: changes color within a few days and clears in one to two weeks. After extensive hematomas, a brownish residue of iron pigment can remain, which is also mistaken for a mark.
- Tyndall effect: a stable bluish tone over a superficial product, with or without relief, unrelated to inflammation.
- Melasma: symmetrical patches linked to hormones and sun, which do not depend on a procedure.
- Erythema: redness that blanches under pressure; in dark skin, it may be barely visible.
How do you prevent it and manage it?
Prevention starts in the assessment: record the phototype and any history of marks, reduce trauma and advise strict sun protection in the following weeks. When a mark appears, management includes sun protection, time and, if needed, topical treatment or a dermatology referral, at the discretion of the qualified professional. Care for pigmented skin is covered in HOF on Black skin.
Also called: PIH, post-inflammatory mark, post-inflammatory hyperchromia, HPI (in Portuguese).
Frequently asked questions
Does a mark after an aesthetic procedure go away on its own?
Post-inflammatory hyperpigmentation usually fades with time, especially with strict sun protection, but it can take months, and the dermal form tends to last longer. Persistent marks should be assessed by a qualified professional, preferably with dermatologic support.
What is the difference between a post-inflammatory mark and the purple of a hematoma?
A hematoma changes color within a few days, from purple to green to yellow, and clears in one to two weeks. A post-inflammatory mark is brownish or gray, appears or persists after the inflammation has passed and evolves over weeks to months.