Post inflammatory hyperpigmentation: causes and treatment
Post inflammatory hyperpigmentation (PIH) is the flat brown, tan or grey mark left behind after your skin has been through some form of trauma or inflammation, whether that is a spot, an eczema flare, a burn or a cosmetic procedure. Most cases involving the outer skin layer fade within several months, though the average resolution time across studies is generally several months, and marks sitting deeper in the dermis can take considerably longer or persist.
Three things matter more than anything else right now:
- Stop the aggravation. No picking, no scrubbing, no aggressive at-home peels on the affected area.
- Wear broad-spectrum sunscreen daily. UV and visible light both darken existing marks and slow recovery.
- Treat what caused it. PIH will not resolve properly while the underlying acne, eczema or irritation is still active.
Key Takeaways
Post inflammatory hyperpigmentation resolves fastest when active inflammation is treated first, sun protection is applied daily, and pigment-targeting actives are introduced gradually and correctly sequenced.
| Point | Details |
|---|---|
| Depth determines timeline | Epidermal PIH often clears within several months; dermal pigment fades more slowly and may persist. |
| Treat the trigger first | Acne, eczema or irritation must be controlled before any lightening treatment can work properly. |
| Confirm PIH, not PIE | Brown or grey marks need pigment treatment; pink or red marks need vascular treatment instead. |
| Photoprotection is non-negotiable | Daily broad-spectrum SPF with visible-light protection prevents existing marks from darkening further. |
| Procedures carry real risk in darker skin | Laser and peels should follow priming and conservative settings, chosen with an experienced clinician. |
| Them-ethod offers calibrated planning | Virtual consultations and the BRIGHT SKY protocol tailor treatment to your Fitzpatrick type and pigment depth. |
Table of Contents
- What is post inflammatory hyperpigmentation and how does it form?
- What causes post inflammatory hyperpigmentation and who is at risk?
- PIH vs PIE: how to tell dark spots from redness
- First-line treatment for hyperpigmentation: what actually works
- When to consider peels, lasers and other procedures
- A practical daily routine to prevent recurring dark spots
- When professional guidance changes the outcome
- Editorial perspective on treating pigmentation safely
- Get a treatment plan built around your skin
- Sources
What is post inflammatory hyperpigmentation and how does it form?
Pigmentation problems like this begin with your melanocytes, the pigment-producing cells sitting at the base of your epidermis. When skin is injured or inflamed, these cells go into overdrive, producing excess melanin that gets transferred, unevenly, into the surrounding keratinocytes. The result is a discoloured patch that outlasts the original injury by weeks, months, or occasionally years.
Where that pigment ends up determines how stubborn it will be.
- Epidermal PIH sits in the upper skin layers. It typically looks light to mid brown, has well-defined edges, and responds relatively well to topical treatment within 6 to 12 months.
- Dermal PIH occurs when pigment (or pigment-laden immune cells called melanophages) drops into the deeper dermis. It tends to look blue-grey or slate coloured, has a hazier border, and improves far more slowly. In some cases it never fully clears.
This distinction is not academic. It explains why two people with what looks like the same dark mark can have completely different experiences with the same cream.
Fitzpatrick skin types III to VI, which cover olive, brown and deeply pigmented skin, carry a disproportionately higher risk of both developing PIH and developing the more persistent dermal variety. A systematic review of 48 studies covering 1,356 participants with skin of colour found that more melanocytes sit closer to the surface and react more readily to inflammatory signals in these skin types, which is precisely why generic pigmentation advice written for lighter skin so often falls short.
What causes post inflammatory hyperpigmentation and who is at risk?
PIH is a reaction, not a disease in its own right. Something inflames the skin first, and the pigment follows.
- Acne is the most frequent trigger. Inflammatory papules and pustules, and especially any you squeeze, leave marks that can persist long after the spot itself has healed.
- Eczema and other inflammatory dermatoses cause chronic low-grade irritation that gradually darkens affected patches.
- Physical trauma, including cuts, insect bites, burns and friction, can all trigger the same melanocyte response.
- Certain medications and photosensitising drugs increase the skin’s reactivity to light and inflammation.
- Cosmetic procedures, including some peels, lasers and microneedling, can paradoxically cause the very pigmentation they were meant to treat if performed too aggressively.
The face bears the brunt of it. Research on skin of colour patients found the majority of PIH cases are localised to the face (https://pmc.ncbi.nlm.nih.gov/articles/PMC11514325/), largely because it is where acne and eczema concentrate and where sun exposure is most constant.
Behaviour matters as much as the original trigger. Picking at a spot, using a scrub or acid too often, or skipping sunscreen after a flare, each reignites low-level inflammation and effectively resets the clock on healing. If you take away one thing from this section, it is that the mark itself is rarely the problem you need to solve. The habit that keeps re-triggering it usually is.
PIH vs PIE: how to tell dark spots from redness
Confusing pigmentation with redness is one of the most common (and costly) mistakes people make, because the two conditions need entirely different treatment.
- PIH shows as brown, tan or grey-black marks caused by excess melanin. It responds to pigment-targeting treatments like hydroquinone or retinoids.
- Post-inflammatory erythema (PIE) shows as pink, red or purple marks caused by lingering dilation of superficial blood vessels rather than pigment. It needs vascular-targeting approaches, not skin lightening agents.
Pressing gently on the mark is a rough home test. If it blanches, or turns paler, under pressure and then returns to colour, you are likely looking at PIE rather than true pigmentation. Clinicians confirm the distinction with tools that go further than the naked eye. A Wood lamp, which uses ultraviolet light, can highlight epidermal pigment that is hard to see under normal lighting, helping to establish whether melanin sits near the surface or deeper in the dermis. When the picture still is not clear, or when a mark behaves unusually, a biopsy settles the question by examining tissue directly. The distinction between PIH and PIE comes down to melanin versus vascular dilation, and getting it right the first time saves months of applying the wrong product.
Pro Tip: If you’ve used a brightening serum for eight weeks with zero change, stop and reconsider the diagnosis before switching products again. You may be treating redness with a pigment-fighting formula, which explains the lack of progress far better than “the product not working” does.
First-line treatment for hyperpigmentation: what actually works
Treatment for hyperpigmentation follows a strict order, and skipping steps rarely ends well.
- Photoprotection comes first, always. Daily broad-spectrum SPF is not optional. UV rays and, in more pigmented skin particularly, visible light both stimulate further melanin production and can undo months of progress in a single unprotected afternoon. Apply roughly a teaspoon’s worth to the face and neck each morning and reapply through the day if you are outdoors, and look for a formula offering visible-light protection alongside UVA/UVB filters. Consensus guidance treats this as foundational to any PIH management plan.
- Topical actives target the pigment itself. Hydroquinone remains one of the most effective agents for interrupting melanin production, typically used at 2% to 4% for a limited course under supervision. Retinoids, including tretinoin and adapalene, speed cell turnover and help disperse existing pigment, though they need to be introduced at lower strengths in darker skin to avoid retinoid dermatitis, which can itself trigger fresh PIH if the skin becomes irritated. Azelaic acid offers a gentler alternative with genuine efficacy and a lower irritation profile. Niacinamide and tranexamic acid both interrupt pigment transfer through separate mechanisms and layer well alongside stronger actives, while antioxidants such as vitamin C support the overall process without directly lightening pigment on their own.
- Combination regimens outperform single ingredients. The Kligman triple combination, hydroquinone paired with tretinoin and a mild steroid, is widely cited in clinical literature on PIH management as more effective than any one ingredient alone. The steroid component should be used for a limited duration to reduce side effects, to avoid its own set of side effects.
Set your expectations around a review conducted across skin-of-colour patients: topical retinoids were used in some studied cases, with partial pigment reduction reported in many but rarely complete clearance(https://pmc.ncbi.nlm.nih.gov/articles/PMC11514325/). Gradual, partial improvement is the realistic outcome for most people using topical therapy alone, particularly where pigment sits in the dermis. If you are considering a procedure later, dermatologists generally recommend priming the skin with a lightening agent for several weeks beforehand to reduce the risk of the procedure itself worsening pigmentation.
When to consider peels, lasers and other procedures
Procedures sit firmly in second place behind topical therapy, and for good reason. Aggressive intervention on already-inflamed or pigment-prone skin can produce more PIH than it resolves, which is precisely the outcome you are trying to avoid.
- Guideline consensus positions topical therapy as first-line, reserving peels and lasers for cases that prove genuinely recalcitrant to months of consistent topical treatment.
- Longer-wavelength devices, such as 1064nm Nd:YAG lasers, and picosecond lasers tend to carry a lower risk profile in darker skin because they place less thermal stress on surrounding tissue.
- Aggressive chemical peels and ablative lasers carry a meaningfully higher risk of triggering new pigmentation in Fitzpatrick III to VI skin, especially when settings are not adjusted conservatively for skin type.
- Priming the skin with a topical lightener for several weeks before any procedure is a recognised way to reduce the odds of post-procedure flare-ups.
The evidence on laser treatment itself is genuinely mixed. In one systematic review, laser therapy was the only modality reported to achieve complete resolution in a subset of treated patients, though results varied(https://pmc.ncbi.nlm.nih.gov/articles/PMC11514325/), yet the same review recorded cases where laser use made pigmentation worse. That range of outcomes is not a flaw in the research. It reflects how much operator skill, device calibration and skin type genuinely change the result.
Pro Tip: Never book a laser or peel for pigmentation from a provider who cannot tell you, unprompted, how they adjust settings for Fitzpatrick IV to VI skin. If they don’t raise it before you ask, that’s your answer.
Clinicians widely favour a “start low, go slow” approach for darker skin, choosing conservative settings and patch testing before committing to a full treatment area. Anyone considering procedural options deserves a clinician who treats caution as a feature, not a delay.
A practical daily routine to prevent recurring dark spots
Preventing new marks matters just as much as treating the ones you already have, and the routine that does this well is simpler than most product marketing suggests.
- Morning: Cleanse gently, apply a treatment serum containing niacinamide or vitamin C, follow with a lightweight moisturiser, then finish with broad-spectrum SPF as the final and non-negotiable step.
- Evening: Cleanse again, apply your prescribed pigment-targeting active (hydroquinone, a retinoid or azelaic acid, but never layer more than one strong active without professional guidance), then moisturise to support the skin barrier while these actives work.
- Weekly: Limit chemical or physical exfoliation to once or twice a week at most, and skip it entirely on any week where skin feels reactive or inflamed.
A structured pigmentation skincare routine built around these steps, rather than a rotating cast of trending products, is what actually moves the needle over months.
Three behavioural rules matter more than any single ingredient: never pick at active spots, never skip sunscreen because it is cloudy, and never introduce a new exfoliating acid the same week you start a new retinoid. Calming formulations, including ingredients like those in the Dermaka range, can support the skin barrier alongside your core actives, though barrier support should complement a pigment-targeting regimen rather than replace it.
When professional guidance changes the outcome
Some cases of post inflammatory hyperpigmentation respond well to a careful over-the-counter routine. Others do not, and knowing which category you fall into early can save you months of the wrong approach.
A personalised assessment is worth pursuing when:
- Pigmentation has not visibly improved after 12 weeks of consistent topical treatment.
- The mark looks blue-grey rather than brown, suggesting dermal pigment that responds differently to standard actives.
- You are planning a peel, laser or microneedling procedure and want your skin primed correctly beforehand.
- You have Fitzpatrick IV to VI skin and want a regimen calibrated to that risk profile from the outset, rather than adjusted after irritation appears.
Them-ethod runs its practice around exactly this kind of tailored approach. Virtual consultations connect you with clinicians who assess your specific pigment depth and skin type before recommending anything, and the BRIGHT SKY protocol structures pigmentation treatment as a staged plan rather than a single product recommendation. For readers whose PIH has procedural roots or needs, in-clinic treatments across London and Athens follow the same conservative, skin-of-colour-aware philosophy covered throughout this guide.
Editorial perspective on treating pigmentation safely
The advice that gets PIH wrong most often is not bad advice exactly, it is advice written for the wrong skin type. Most viral skincare content assumes fair skin, rapid results and high-strength actives, which is precisely the combination that makes darker skin worse rather than better.
What the evidence actually supports is patience and restraint. A systematic review found partial improvement was the most common outcome across nearly every treatment studied, not the dramatic before-and-after transformation people are chasing. That gap between expectation and evidence is where most self-treatment goes wrong, usually through over-exfoliation or an unsupervised jump straight to lasers.
If I had to prioritise one thing for readers with PIH, it would not be a product. It would be sequencing: control the inflammation first, protect from light religiously, then introduce pigment-targeting actives slowly enough that irritation never becomes the next trigger. Skin of colour deserves treatment plans built around its actual biology, not adapted from someone else’s.
— Jess
Get a treatment plan built around your skin
Them-ethod is the alternative to guesswork-driven, one-size-fits-all pigmentation shopping: instead of piecing together hydroquinone here and a retinoid there, you get a clinician-assessed plan calibrated to your specific pigment depth and Fitzpatrick type before you spend a penny on product. That matters most for anyone with skin of colour, where the wrong strength or sequencing is what actually causes new marks rather than fading old ones.
As a UK-based Obagi Ambassador Clinic offering both virtual consultations and in-clinic treatment across London and Athens, Them-ethod builds regimens around the BRIGHT SKY protocol rather than trends. If your dark spots have resisted months of DIY effort, or you are weighing a procedure and want your skin primed correctly first, book a virtual skin consultation and get a plan suited to how your skin actually behaves. Readers weighing up the practice’s track record can also see client outcomes and reviews before booking.
Sources
- Postinflammatory Hyperpigmentation - StatPearls - NCBI Bookshelf
- Treatment of Post‑Inflammatory Hyperpigmentation in Skin of Colour: A Systematic Review - PMC
- Melanin hyperpigmentation disorders, management: global 2025 guideline summary - Medscape
This article is general information, not a substitute for advice from a qualified doctor. Consult a qualified healthcare professional about your own circumstances before acting on anything here.
%20is%20the%20flat%20brown,%20tan%20or%20grey%20mark%20left%20behind%20after%20your%20skin%20has%20been%20through%20some%20form%20of%20trauma%20or%20inflammation,%20whether%20that%20is%20a%20spot,%20an%20eczema%20f...){kind=link}