What Is Melasma? Causes, Triggers and Symptoms

What Is Melasma? Causes, Triggers and How It Differs From Other Pigmentation

Melasma is a common, harmless skin condition that causes dark, discoloured patches, usually brown or grey-brown, to appear on the face. It is one of the most misunderstood skin concerns too, as many people notice these patches and assume they are simply sun damage or general ageing, when in fact melasma has its own distinct causes and pattern of behaviour.

This guide explains what melasma is, what triggers it, and how it differs from other types of facial pigmentation such as sun spots and post-inflammatory marks. Understanding the difference matters, because the right approach for one type of pigmentation is not always right for another.

What Is Melasma?

Melasma is a common skin condition that causes patches of darker pigmentation to develop on the face. It typically appears as flat, irregular areas of brown or greyish-brown discolouration, most commonly on the cheeks, forehead, upper lip, nose and chin.

Unlike sun spots, which tend to be more defined and localised, melasma on the face usually presents as larger, more diffuse patches that sit symmetrically on both sides of the face. This symmetry is one of its most recognisable characteristics.

Melasma is far more common in women than men, and is particularly prevalent in those with medium to dark skin tones, though it can affect all skin types. It is not harmful, but for many people it has a noticeable impact on how they feel about their skin.

It also tends to be a chronic condition. Without an understanding of what is driving it, melasma often returns or worsens after periods of improvement, which is part of why it has such a reputation for being stubborn. The British Association of Dermatologists provides further detail on melasma as a recognised skin condition for anyone who would like to read more from a clinical source.

What Causes Melasma: Understanding Its Triggers

Melasma develops when melanocytes, the cells responsible for producing melanin in the skin, become overactive and produce excess pigment in localised areas. Several factors are known to trigger or worsen this overactivity.

• UV exposure: Sunlight is the most significant trigger for melasma. UV radiation stimulates melanocyte activity, which is why melasma typically worsens during summer months and improves in winter.
• Hormonal changes: Oestrogen and progesterone appear to sensitise melanocytes to UV exposure. This explains why melasma is so common during pregnancy, when it is sometimes called the mask of pregnancy, and in those using hormonal contraception or hormone replacement therapy.
• Genetics: A family history of melasma increases the likelihood of developing it. Those with a genetic predisposition tend to find it more persistent and harder to clear.
• Heat: From the sun, hot environments and even certain light sources, heat can trigger melasma independently of UV exposure, which is why some people find it worsens even when SPF is consistently applied.
• Skin inflammation: Injury or inflammation in the skin can also trigger a related but distinct form of pigmentation, post-inflammatory hyperpigmentation, which can appear alongside or be mistaken for melasma.

This combination of triggers is part of what makes melasma more complex than most other forms of facial pigmentation. It is rarely caused by just one factor, and addressing it usually means understanding which of these triggers is most relevant to the individual.

Melasma vs Hyperpigmentation: Knowing the Difference

Not all facial pigmentation is the same, and melasma is often confused with other, more general forms of hyperpigmentation. The distinction matters, because what works for one does not necessarily work for another, and in some cases the wrong approach can make pigmentation worse.

• Sun spots (solar lentigines): Flat, well-defined dark spots caused by cumulative UV exposure over time. They tend to be more localised than melasma and do not follow its hormonal pattern.
• Post-inflammatory hyperpigmentation (PIH): Darkening that occurs at the site of previous skin inflammation or injury, such as acne, a cut or a burn. PIH does not follow the symmetrical distribution that is characteristic of melasma.
• Freckles: Small, flat spots caused by a genetic tendency for melanin to cluster in certain areas with sun exposure. They are generally lighter and more uniform than melasma patches.

A clinical skin assessment is the most reliable way to distinguish between these. The depth, pattern and distribution of the pigmentation, alongside a person’s history, all help determine exactly what is present and how it should be approached.

How Can Melasma Be Treated?

Melasma is generally managed rather than instantly cured, and the most effective approach tends to combine three things: addressing the pigmentation itself, identifying and managing its triggers, and maintaining the improvement over time.

Clinically, this can involve laser treatments that target excess melanin, such as LaseMD Ultra or DermaV, professional skin peels, and prescription-grade skincare containing ingredients like retinoids and vitamin C. Daily sun protection plays a central role in any melasma management plan, since UV exposure is one of its main triggers.

Because melasma responds differently from person to person, and because the wrong treatment can occasionally worsen it, a proper skin assessment is the right starting point before deciding on any approach. If you would like to explore melasma treatment options in more depth, we have a dedicated guide covering the clinical treatments available.

Why Understanding Melasma Matters

Melasma is frequently mistaken for sun damage or general ageing, which often leads people toward treatments or products that were never designed for it. Understanding what melasma is, and what makes it different from other types of pigmentation, is the first step toward managing it properly.

If you are noticing patches of darker, symmetrical pigmentation on your face, particularly if they tend to worsen in summer or appeared during pregnancy or while using hormonal contraception, it is worth having your skin properly assessed rather than guessing at the cause.

Conclusion

Melasma is a distinct, hormonally influenced form of facial pigmentation that behaves differently from sun spots or general hyperpigmentation. Recognising what it is, and what triggers it, makes it far easier to manage effectively over time.

If you think you may have melasma and would like a professional assessment, Amanda Azzopardi Aesthetics offers skin consultations to help identify exactly what you are dealing with and what the most appropriate next steps would be.

Contact us today for a clinical skin assessment

MEET THE AUTHOR

Amanda Azzopardi, an Advanced Nurse Practitioner and Aesthetic Medicine Prescriber, specialises in ageing-related changes. With a Masters in Advanced Clinical Practice, she's trained at the renowned Harley Academy in London and the Level 7 accredited Derma Medical Academy. Boasting over 15 years of global experience in acute medical settings and extensive aesthetic insurance, Amanda combines care, skill, and professionalism to ensure your treatments are in trustworthy hands.