Pigmentation is one of the most common skin concerns, but not all pigmentation is the same. Melasma, post-inflammatory hyperpigmentation, freckles and sun spots can look similar while having very different causes and treatment considerations. Understanding what is happening within the skin is an important first step towards managing uneven skin tone safely and effectively. At Woulfe Skin Specialists, we take a personalised, skin-first approach to pigmentation. Rather than treating every brown mark in the same way, we first assess the type of pigmentation, the condition of the skin barrier and the factors that may be contributing to it.
What is melanin?
Melanin is an essential part of healthy skin. It gives our skin, hair and eyes their colour and provides some natural protection against ultraviolet radiation. Pigmentation becomes a concern when melanin production or distribution becomes uneven, resulting in areas that appear darker than the surrounding skin.
This can occur following:
- Sun exposure
- Inflammation
- Hormonal changes
- Skin injury
- A combination of these factors
Importantly, pigmentation is not one single condition. Identifying the type of pigmentation is essential because different forms can have different causes and may respond differently to treatment.
How is melanin produced?
Melanin is produced by specialised cells called melanocytes, which are primarily located in the basal layer of the epidermis. Melanin is manufactured inside structures called melanosomes. These pigment-containing structures are transferred from melanocytes to surrounding keratinocytes, the cells that make up most of the outer skin. Once transferred, melanin forms a protective cap around the nucleus of the keratinocyte. This helps absorb and disperse some ultraviolet radiation before it can reach and damage cellular DNA.
Do darker skin tones have more melanocytes?
People with different skin tones generally have broadly similar numbers of melanocytes in comparable areas of the body. Differences in visible skin colour are influenced by several factors, including:
- The type and amount of melanin produced
- The size and distribution of melanosomes
- How melanosomes are transferred to keratinocytes
- How quickly melanosomes are broken down
- Genetic regulation of melanogenesis
- The skin's response to ultraviolet radiation, inflammation and hormones
This is why pigmentation risk cannot be assessed simply by counting melanocytes or assigning someone to an ethnic category.
Eumelanin and pheomelanin
The two principal forms of melanin are eumelanin and pheomelanin.
Eumelanin
Eumelanin is a brown-to-black pigment. It absorbs ultraviolet radiation more efficiently and generally provides greater photoprotection.
Pheomelanin
Pheomelanin is a yellow-to-red pigment. It provides less ultraviolet protection and, under certain conditions, may contribute to oxidative stress. The balance between these forms is influenced partly by the melanocortin-1 receptor (MC1R). Variations in the MC1R gene help explain some differences in hair colour, skin colour, tanning response and sensitivity to ultraviolet damage. However, naturally darker skin is not completely protected from sun damage. Melanin provides partial biological protection, but it does not prevent photoageing, hyperpigmentation, DNA damage or skin cancer. Every skin tone therefore requires appropriate photoprotection.
How does melanin production work?
The production of melanin is known as melanogenesis. It begins with the amino acid tyrosine. An enzyme called tyrosinase converts tyrosine through a series of chemical steps into melanin.
A key signalling pathway involves:
- Ultraviolet exposure or another stimulus affecting the skin
- Release of signalling molecules, including alpha-melanocyte-stimulating hormone
- Binding of this hormone to the MC1R receptor on the melanocyte
- Activation of cyclic AMP and related cellular signals
- Increased activity of MITF, a transcription factor involved in melanocyte function
- Increased expression of tyrosinase and other melanogenic enzymes
- Production and transfer of melanin-containing melanosomes
Pigmentation is therefore not controlled by one enzyme or one type of cell. Keratinocytes, melanocytes, fibroblasts, inflammatory cells, blood vessels, hormones and signalling molecules can all influence the process.
How does sunlight affect pigmentation?
Sunlight contains both ultraviolet radiation and visible light, and both can be relevant when managing pigmentation.
UVB
UVB acts predominantly within the epidermis and is strongly associated with sunburn and direct DNA damage. It can also activate pathways that increase melanogenic signalling, encouraging melanocytes to produce additional melanin. A tan is therefore a biological response to ultraviolet exposure — it is not evidence that the skin has been safely strengthened.
UVA
UVA penetrates more deeply into the skin and contributes to oxidative stress, persistent pigment darkening and photoageing. UVA can reach the skin through clouds and some types of window glass. For this reason, pigmentation management needs to consider UVA as well as UVB. A high SPF number alone does not fully describe UVA protection.
Visible light
Visible light, particularly shorter blue-violet wavelengths present in sunlight, can contribute to longer-lasting pigmentation in some skin types. This appears particularly relevant in melasma and in medium-to-deeper skin tones. The sun is a much stronger source of visible light than phones or computer screens, and current evidence does not justify creating unnecessary anxiety around ordinary screen use. Tinted sunscreens containing suitable iron oxides can provide additional protection against visible-light-induced pigmentation.
Pigmentation is not one diagnosis
Before beginning treatment, it is important to establish what is causing the discolouration.
Melasma
Melasma commonly appears as symmetrical brown or grey-brown patches, frequently affecting the:
- Cheeks
- Forehead
- Upper lip
- Jawline
It is a chronic, relapsing condition influenced by multiple factors, including:
- Ultraviolet and visible-light exposure
- Genetic susceptibility
- Pregnancy and hormonal influences
- Certain hormonal medicines
- Inflammation and oxidative stress
- Vascular and dermal changes
- Changes around the basement membrane
- Repeated heat or light exposure in susceptible individuals
Melasma is more complex than an accumulation of surface pigment. Changes can involve the epidermis, basement membrane, dermis, blood vessels and communication between different skin cells. For this reason, aggressive exfoliation or heat-based treatments can sometimes make melasma worse. Successful management usually requires long-term suppression and maintenance rather than the promise of a permanent cure.
Post-inflammatory hyperpigmentation
Post-inflammatory hyperpigmentation (PIH) develops after inflammation or injury.
Common triggers include:
- Acne
- Eczema or dermatitis
- Picking or squeezing blemishes
- Burns
- Waxing or friction
- Insect bites
- Irritating skincare
- Over-exfoliation
- Treatments that cause excessive inflammation
Inflammatory signals can stimulate melanocyte activity. If inflammation disrupts the junction between the epidermis and dermis, pigment may also move into the dermis, where it can become more persistent. PIH can affect every skin tone but is often more noticeable and longer-lasting in medium-to-deeper skin tones. The first priority is to control the original inflammation. Attempting to remove pigmentation while acne, dermatitis or irritation remains active can perpetuate the problem.
Solar lentigines
Solar lentigines are well-defined areas of pigmentation associated with cumulative ultraviolet exposure. They are commonly referred to as sun spots or age spots. They often appear on the face, hands, chest and other regularly exposed areas. Selected lentigines may respond to targeted treatment, but diagnosis must come first. An unusual or changing lesion should never be treated as a cosmetic sun spot without appropriate medical assessment.
Freckles
Freckles, or ephelides, are usually genetically influenced and become darker following ultraviolet exposure. They may fade when sun exposure decreases. Freckles are different from solar lentigines, although both may respond visibly to changes in ultraviolet exposure.
The role of inflammation and the skin barrier
The condition of the skin barrier plays an important role in pigmentation management. A compromised skin barrier can increase water loss and make the skin more vulnerable to irritants. This can sustain inflammatory signalling and increase the likelihood of pigmentation following treatment or injury. This is why a barrier-first approach is important. Using multiple acids, scrubs, retinoids and pigment products together does not necessarily produce faster results. Excessive irritation can create more inflammation and potentially more pigmentation. Before introducing corrective ingredients or procedures, the skin may first need:
- Gentle cleansing
- Appropriate moisturisation
- Barrier-supporting lipids
- Reduction of irritating products
- Control of acne, eczema or dermatitis
- Consistent photoprotection
Ingredients used in pigmentation programmes
Different ingredients can act at different points in the pigment pathway.
Vitamin C
Vitamin C is an antioxidant that can help reduce oxidative stress and influence tyrosinase activity. Its performance depends on the form of vitamin C, concentration, formulation, stability, pH and individual tolerance. Not every product labelled as vitamin C delivers the same biological activity.
Niacinamide
Niacinamide may help reduce the transfer of melanosomes from melanocytes to keratinocytes. It can also support the skin barrier and may be useful where pigmentation occurs alongside sensitivity.
Azelaic acid
Azelaic acid can influence tyrosinase activity and abnormal melanocyte function. It may be useful where pigmentation occurs alongside acne, inflammation or rosacea, although individual tolerance needs to be assessed.
Retinoids
Retinoids influence cell turnover and can support the distribution and removal of epidermal pigment. They may also improve the penetration of other ingredients. However, excessive or poorly introduced retinoid use can cause irritation and potentially worsen post-inflammatory pigmentation. Retinoids should therefore be introduced gradually and may not be appropriate during pregnancy.
Tranexamic acid
Topical tranexamic acid is used in some pigmentation formulations and may influence pathways linking ultraviolet exposure, inflammation and melanocyte activity. Oral tranexamic acid is different. It is a medical treatment with potentially serious contraindications, including thrombotic risk, and should never be used for pigmentation without appropriate medical assessment and prescribing. Other pigment-regulating ingredients may include cysteamine, kojic acid, alpha-arbutin, thiamidol and selected exfoliating acids. The goal is not to eliminate melanocytes or remove normal skin colour. Instead, the objective is to regulate excessive or uneven pigment production while maintaining skin-barrier health.
Photoprotection: the foundation of pigmentation management
Corrective treatment is unlikely to succeed if the skin continues to receive the signals that stimulate pigmentation. For melasma or recurrent pigmentation, consider:
- Broad-spectrum SPF 50+ sunscreen
- Strong UVA protection
- A tinted formulation containing iron oxides where visible light is relevant
- Generous and even application to the face, ears, neck and other exposed areas
- Reapplication during prolonged outdoor exposure and after swimming or perspiration
- A wide-brimmed hat and protective clothing
- Seeking shade when ultraviolet radiation is strongest
- Avoiding sunbeds
- Avoiding unnecessary heat exposure if heat consistently worsens melasma
No sunscreen provides complete protection. Sunscreen should be combined with shade, protective clothing and sensible exposure habits. In Ireland, skin can still be damaged on cloudy days, making daily protection particularly important for anyone managing melasma, PIH or recurrent sun-induced pigmentation.
Professional pigmentation treatment
Professional pigmentation treatment should begin with consultation rather than a procedure. At Woulfe Skin Specialists, assessment may include:
- Relevant medical and medication history
- Pregnancy or hormonal history where applicable
- Previous skin reactions and treatment history
- Examination of the pigmentation pattern
- Skin-barrier assessment
- Standardised photographs
- Review of current skincare and sunscreen use
- Identification of possible contraindications
- Referral to a GP or dermatologist where required
Depending on the diagnosis, skin type and barrier condition, a programme may combine homecare with selected professional treatments. Chemical peels, microneedling, light-based procedures and other technologies are not automatically appropriate for every type of pigmentation. Excessive heat, inflammation or injury can aggravate melasma or cause PIH, particularly in pigment-prone skin. IPL may be considered for appropriately assessed sun-induced pigmentation, but it is not a universal treatment for melasma. Conservative settings, patch testing, preparation and aftercare are essential.
The Woulfe Method for pigmentation
At Woulfe Skin Specialists, our approach follows four stages:
1. Support
Stabilise the skin barrier, reduce inflammation and establish a routine that the skin can tolerate.
2. Protect
Use appropriate UVA, UVB and, where relevant, visible-light protection consistently.
3. Correct
Introduce selected pigment-regulating ingredients and professional treatments based on the type and depth of pigmentation.
4. Prevent
Maintain results by controlling triggers, treating inflammation early and continuing daily photoprotection.
Pigmentation usually develops over time. Its management also requires time, consistency and realistic expectations.
When does pigmentation need medical assessment?
Not every brown or dark mark is simply a cosmetic pigmentation concern. A lesion should not be treated cosmetically if it is new, changing, irregular or unexplained. A GP or dermatologist should assess a mole or pigmented lesion showing signs of the ABCDE warning system:
- A — Asymmetry: one half looks different from the other
- B — Border: irregular, blurred or uneven edges
- C — Colour: more than one colour or an unusual change in colour
- D — Diameter: increasing size, particularly when larger than approximately 6 mm, although melanoma can be smaller
- E — Evolving: changing in size, shape, colour, sensation or behaviour
A lesion that bleeds, crusts, repeatedly itches, fails to heal or looks different from a person's other moles should also be medically examined. A skin clinic should not treat a suspicious lesion with a peel, laser or light-based device. Medical diagnosis must come first.
A realistic approach to pigmentation
Pigmentation can often be significantly improved, but recurrence is common when the underlying triggers remain active. The goal is not to suppress healthy melanin or promise permanently pigment-free skin. Instead, the aim is to understand why excess pigment is being produced, reduce avoidable triggers and support a more even, resilient complexion without compromising skin health. A personalised consultation allows us to distinguish between melasma, post-inflammatory pigmentation, sun-induced changes and conditions requiring medical referral and to build a safe plan around the individual rather than treating every brown mark in the same way.
Book a Pigmentation Consultation
If you're concerned about pigmentation or uneven skin tone, our skin specialists can assess your skin and help determine the most appropriate treatment and skincare approach for you.
Book a consultation with Woulfe Skin Specialists to begin a personalised pigmentation plan.
References
-
D’Mello SAN, Finlay GJ, Baguley BC, Askarian-Amiri ME. Signaling Pathways in Melanogenesis. International Journal of Molecular Sciences. 2016.
-
Snyman M et al. The metabolism of melanin synthesis—from melanocytes to keratinocytes. Pigment Cell & Melanoma Research. 2024.
-
Rajanala S, Maymone MBC, Vashi NA. Melasma pathogenesis: a review of the latest research, pathological findings and investigational therapies. Dermatology Online Journal. 2019.
-
Castanedo-Cazares JP et al. Near-visible light and UV photoprotection in the treatment of melasma: a double-blind randomized trial. Photodermatology, Photoimmunology & Photomedicine. 2014.
-
Boukari F et al. Prevention of melasma relapses with sunscreen combining protection against UV and short wavelengths of visible light. Journal of the American Academy of Dermatology. 2015.
-
Dumbuya H et al. Impact of iron-oxide-containing formulations against visible-light-induced skin pigmentation in skin-of-colour individuals. Journal of Drugs in Dermatology. 2020.
-
Mar K et al. Treatment of post-inflammatory hyperpigmentation in skin of colour: a systematic review. Journal of Cutaneous Medicine and Surgery. 2024.
-
Health Service Executive. How to protect your skin from the sun and sunbeds.
-
Health Service Executive. Skin cancer — melanoma symptoms and the ABCDE checklist.
