Sunspots or Post-Inflammatory Hyperpigmentation (PIH)? How to Tell the Difference

Sunspots and post-inflammatory hyperpigmentation (PIH) can look very similar at first glance, but they differ significantly in their causes, risk factors and treatment. Dermatologists Dr. med. Christine Schrammek-Drusio and Christina Drusio explain what is important when identifying pigmentation, how it can be prevented and treated, and where the boundaries lie between cosmetic and medical treatment.

What is the difference between sunspots and PIH?

Dr. med. Christine Schrammek-Drusio:Sunspots develop as a result of chronic UV exposure. They are usually clearly defined, light to dark brown in colour, and typically appear on sun-exposed areas such as the face, décolleté and backs of the hands.

Post-inflammatory hyperpigmentation (PIH), on the other hand, develops following inflammation — for example after acne, eczema, burns, aggressive peels, laser or IPL treatments, or manipulation of the skin. The shape and distribution of PIH generally follow the pattern of the preceding inflammation.

Important diagnostic criteria include the client’s history, distribution and colour of the pigmentation, its development over time and dermatoscopy.

If a lesion is unclear or atypical, it should be assessed by a dermatologist to rule out melanocytic lesions, including early non-invasive forms of melanoma such as lentigo maligna.

Which skin types are most affected?

Christina Drusio:PIH can affect all skin types, but it tends to be more common, pronounced and persistent in more highly pigmented skin, particularly Fitzpatrick skin types III–VI. This is because melanocytes in these skin types can respond more strongly to inflammatory stimuli.

Sunspots, meanwhile, tend to increase with long-term UV exposure and become more common from around the age of 40. In lighter skin types, particularly Fitzpatrick I and II, they may appear earlier and be more visibly noticeable.

What are the recommended treatment approaches?

For the best possible results, a combined or multimodal approach is recommended. This may include consistent sun protection, topical active ingredients and, where appropriate, medically supervised peels, laser or IPL.

The appropriate approach depends on the diagnosis, skin type, depth of pigmentation and the skin’s tendency towards inflammation.

In medical dermatology, picosecond lasers and thulium lasers are becoming increasingly important. Picosecond lasers specifically fragment pigment particles, while thulium lasers can create tiny microchannels in the skin, allowing topical ingredients such as tranexamic acid to penetrate more deeply.

When treating PIH, controlling the underlying cause — such as acne or eczema — should come first.

Medical laser treatments and certain active ingredients, including prescription retinoids and hydroquinone, remain the responsibility of medical professionals.

Beauty therapists should not make medical diagnoses, treat pathological skin changes or use prescription medicines. Before any cosmetic treatment is performed, melanocytic changes must first be ruled out.

Which topical ingredients can help reduce pigmentation?

Dr. med. Christine Schrammek-Drusio:Cosmetically established ingredients include:

• Niacinamide

• Vitamin C

• Azelaic acid derivatives

• Glabridin

• Arbutin

For the best possible results, it is important to address several stages of the pigmentation process simultaneously — from melanocyte stimulation and melanin synthesis through to melanin transfer.

Anti-inflammatory and antioxidant ingredients should also form part of the treatment approach.

In dermatology, ingredients such as hydroquinone, retinoids and azelaic acid, as well as medically supervised combination preparations, are commonly used.

Prevention is essential — especially with PIH

Christina Drusio:The highest priority for both sunspots and PIH is daily broad-spectrum SPF 50+ sun protection.

Sunscreen should be applied in sufficient quantity and combined with additional protective measures such as wearing a hat and sunglasses, seeking shade and avoiding the midday sun.

Following peels, microneedling or device-based treatments, depending on the intensity of the procedure, the skin may require several weeks of particularly careful protection. During this time, sun exposure, heat, sauna and irritating active ingredients should be avoided until the skin barrier has stabilised.

Products containing ceramides and panthenol, as well as antioxidant serums, can provide useful support during this period.

Beauty professionals play an important role in guiding clients through correct post-treatment care.

When it comes to PIH, prevention is particularly important: inflammatory triggers should be kept to a minimum, unnecessary manipulation of the skin should be avoided, and early reactions following treatment should be addressed promptly.

What should you do if the skin reacts after an aesthetic treatment?

Dr. med. Christine Schrammek-Drusio:If severe redness or burning occurs during treatment, the treatment should be stopped immediately.

The skin should then be calmed with gentle cooling and barrier-supporting skincare, while avoiding any further irritation.

If early signs of PIH develop in the following days, consistent sun protection and gentle skincare designed to stabilise the skin barrier — for example products containing ceramides or panthenol — are recommended.

The aim should be to treat the skin gently rather than trying to counteract the pigmentation aggressively with stronger peels or irritating active ingredients.

If blistering, crusting, pain, persistent severe redness, weeping or signs of infection occur, a dermatologist should always be consulted.

How can the success of pigmentation treatment be measured?

Meaningful progress photography requires consistent conditions. The camera, lighting, distance, angle and time of day should ideally remain the same for each photograph.

Standardised imaging systems such as VISIA can provide greater reproducibility, while devices such as Mexameters or Chromameters can objectively measure melanin or erythema levels.

In dermatological practice, validated scoring systems such as MASI/mMASI for melasma and PIH severity indices can also help monitor progress.

Documentation should be carried out at clearly defined intervals — for example after four, eight and twelve weeks — while also taking seasonal changes into account.

Common mistakes when treating pigmentation

Dr. med. Christine Schrammek-Drusio:One common mistake is beginning with treatments that are too aggressive, without allowing the skin sufficient time to adapt and without consistent UV protection.

Other risks include combining too many active ingredients at once, treating already inflamed skin, and performing laser or IPL treatments on tanned or unsuitable skin.

A thorough client consultation before treatment is also essential. Important considerations include pregnancy and the use of medications or supplements that may increase photosensitivity, such as certain antibiotics, St John’s Wort or vitamin A preparations. Recent acne treatment with medications such as isotretinoin must also be considered.

Treating pigmentation that has not been medically assessed when necessary, or allowing too little time between treatments, can also create problems.

At home, excessive exfoliation, combining incompatible active ingredients — such as retinol with strong acids — inconsistent sun protection, stopping treatment too early and manipulating the skin can all contribute to unwanted reactions.

Unrealistic expectations may also lead to overtreatment. A gradual approach combined with patience is usually the better option.

What does the latest research tell us?

Christina Drusio:Pigmentation treatment is increasingly moving towards skin-barrier-friendly, low-inflammation approaches, with greater emphasis on preparing the skin, appropriate aftercare and combining gentle active ingredients rather than creating maximum irritation.

There is also growing interest in the role of the skin microbiome. A balanced microbiome may contribute to limiting PIH through immune signalling pathways, further highlighting the importance of gentle, microbiome-friendly skincare during aftercare.

Current evidence also suggests that pigmentation is influenced not only by UV radiation, but also by visible light and blue light, which may stimulate melanogenesis. Tinted sunscreens containing iron oxides can therefore provide broader protection than traditional UV filters alone.

Home care is key to long-term success

Christina Drusio:The long-term success of pigmentation treatment depends heavily on home care.

Results often depend less on individual treatments and more on a consistent skincare routine. Visible improvements take time — generally 12–16 weeks — and require patience and commitment.

Daily high-level sun protection, a stable skin barrier, anti-inflammatory ingredients and realistic expectations are essential.

Beauty professionals have an important role to play throughout this process. They can guide clients in the correct use of products, recognise signs of over-irritation early and refer clients to a dermatologist when necessary.

About the Experts

Dr. med. Christine Schrammek-DrusioManaging Director of Dr. med. Christine Schrammek Kosmetik GmbH, dermatologist and allergologist. As an anti-ageing expert, she develops professional treatment methods, including the GREEN PEEL® Herbal Peeling Treatment, as well as dermatological skincare products.

Christina DrusioA member of the owning family and management team of Dr. med. Christine Schrammek Kosmetik GmbH. She is a specialist in dermatology and a recognised skin expert and speaker at international lectures and seminars.

Originally published in BEAUTY FORUM, March 2026. English adaptation published in New Zealand with permission from Dr. med. Christine Schrammek Kosmetik.

References

1. Auffret N, Leccia MT, Ballanger F, Claudel JP, Dahan S, Dréno B. Acne-induced Post-inflammatory Hyperpigmentation: From Grading to Treatment. Acta Derm Venereol. 2025;105.

2. Minasyan M, Hogan S, Lal K. Oral Tranexamic Acid for Prevention and Treatment of Postinflammatory Hyperpigmentation. Dermatol Surg. 2024;50(12S)–S224.