What Causes Melasma, Its Types, and How to Fade It

Melasma comes from several factors at once, especially sun exposure (both UV rays and visible light), hormonal changes, heat, genetics, and some medications. Medically it is broadly classified by pigment depth into epidermal, dermal, and mixed melasma. Today melasma can be faded and controlled with sun protection, topicals, and laser as assessed by a doctor, but it is a chronic condition that can recur. Results vary by individual.

What Causes Melasma

Melasma occurs when the pigment-producing cells (melanocytes) in the skin become overactive and deposit melanin as brown to grayish-brown patches. These usually appear symmetrically on both sides of the face, over the cheekbones, forehead, bridge of the nose, and above the upper lip. The key point is that melasma almost never comes from a single cause; it is the combined result of several triggers acting together.

According to the American Academy of Dermatology (AAD) and DermNet, the factors commonly involved in melasma include:

• Sun exposure is the single most important trigger, including UVA/UVB rays and visible light, especially blue light from the sun, which drives pigment cells to work harder and can make melasma darker or bring it back.
• Hormonal changes such as pregnancy (which is why melasma in pregnancy is sometimes called the “mask of pregnancy”), birth-control pills, or hormone therapy. Estrogen and progesterone play a role in stimulating pigment, which is why melasma is clearly more common in women than in men.
• Heat accumulated on the face, for example from cooking over a stove, saunas, or very hot weather, can stimulate pigment even without direct sun.
• Genetics means people with a family history of melasma are more prone to it, and it is more common in people with darker, Asian skin tones.
• Certain medicines and substances that make the skin more sensitive to light, along with irritating cosmetics or products, can be triggers in some people.

Because melasma usually stems from several factors at once, care is not about fixing a single thing but about controlling multiple triggers, with consistent sun protection as an indispensable foundation.

How Many Types of Melasma Are There

In practice, doctors classify melasma by pigment depth into three main groups, because depth directly affects the choice of treatment and how expectations are set. Melasma with shallower pigment is generally easier to fade than melasma with deeper pigment.

• Epidermal melasma: the pigment is in the epidermis, usually appears as a fairly distinct brown with a somewhat noticeable border, and this group tends to respond to topicals and care better than the others.
• Dermal melasma: the pigment lies down in the dermis, usually appears grayish or grayish-brown with an indistinct border, and this group is usually harder to fade and takes longer.
• Mixed melasma: has pigment in both the superficial and deep layers, and is the most commonly seen in the clinic, so care usually requires several methods together.

Beyond depth, doctors also consider the triggers involved, such as hormone-related melasma during pregnancy or with medication, which may partly fade on its own once the trigger is gone. The table below summarizes the main differences (this is general information, not a substitute for a doctor’s diagnosis).

What Is the Difference Between Sun-Related and Deep Melasma

Many people are familiar with the everyday terms “sun-related melasma” and “deep melasma,” which help communication but do not map exactly onto the medical classification. “Sun-related melasma” usually means melasma clearly linked to sun exposure with shallow pigment, so it often corresponds to epidermal melasma. “Deep melasma” refers to pigment that has gone down into the dermis, tends to look grayish, and is harder to fade.

A point to watch for is that deep melasma is sometimes confused with “Hori’s macules,” which are a different condition. Hori’s macules are dermal pigment spots that call for a different treatment approach from melasma. If you want to understand the differences among melasma, freckles, and dark spots in detail, read our article on melasma, freckles, and dark spots.

In reality, one person may have both epidermal and dermal melasma mixed together, or melasma alongside freckles on the same face, so telling them apart by eye is difficult. Doctors rely on examining the appearance and depth, and sometimes use tools such as a Wood’s lamp, to assess before planning treatment.

How to Fade Melasma

The current approach to melasma aims to fade it and keep it from darkening rather than expecting it to disappear in a single session, because melasma is a chronic condition that can recur. Doctors usually combine several methods and adjust them to the type of melasma and each person’s skin. The main options commonly considered are:

• Sun protection is the most important foundation and part of the treatment, not just prevention, because no matter how well other methods work, unprotected sun exposure can make melasma darken again.
• Topicals: a doctor may consider topical agents that help even out skin tone, such as ingredients that reduce pigment production. They should be used under a doctor’s guidance, because some have limitations and side effects that need monitoring.
• Adjunctive oral medication: in some stubborn cases, a doctor may consider supportive agents such as tranexamic acid, which has evidence supporting its use as an adjunct in some people, but indications and contraindications must always be assessed by a doctor first.
• Pigment laser such as Pico Laser or Q-switch is an option a doctor may consider in some cases, especially melasma that does not respond enough to topicals, but the energy setting must be chosen carefully and the treatment carried out by an experienced doctor.

What should be understood in common is that no single method suits everyone with melasma. Combining several methods under a doctor’s assessment usually works better than choosing a method based on hearsay. You can read more about pigmentation treatment with Pico Laser on our service page.

How Much Can Melasma Laser Help, and What to Watch For

Melasma laser is a supportive tool that may help fade melasma in some cases, but it is not the answer for every type of melasma, and it must be used with more caution than usual, because melasma is sensitive to stimulation. Using energy that is too high or unsuited to the skin can trigger the melasma to darken or lead to post-inflammatory dark marks.

Pico lasers deliver energy in ultra-short picosecond pulses to help break pigment into smaller particles while reducing heat build-up in the surrounding skin. For melasma, doctors usually choose low energy and proceed gradually, generally as a course of several sessions spaced about 3 to 4 weeks apart, always combined with sun protection and topicals. The right number of sessions varies from person to person.

Before deciding on melasma laser, consider the following:

• Have a doctor assess the type and depth of your melasma first, because dermal and mixed melasma respond differently from epidermal melasma.
• Understand that laser is part of a long-term plan, not a treatment that finishes in a single session.
• Follow aftercare instructions, especially strict sun protection, to reduce the chance of melasma darkening again.

If you want to understand how Pico laser works and which skin problems it suits, read more in our article on what Pico laser is.

How Long Until Melasma Shows Results

A common question is “how long until melasma treatment shows results.” The honest answer is that melasma takes time and consistency. In general, a change is usually seen after several weeks to months of consistent care, not immediately after the first session, and the timeline varies widely from person to person.

Factors that affect the timeline and results include:

• The type and depth of the melasma: epidermal melasma usually shows change faster than dermal and mixed melasma.
• Consistency of sun protection: people who protect strictly against the sun tend to see better results that last longer.
• Following the doctor’s plan: using topicals and keeping appointments consistently directly affects the outcome.
• Triggers that remain: such as hormones or accumulated heat, which can slow the fading.

For this reason, setting realistic expectations matters. Melasma can be faded and controlled, but it is usually not a one-and-done matter. The doctor will reassess periodically and adjust the plan to suit the changing skin. Results vary by individual.

Why Melasma Recurs and How to Prevent It

Melasma can recur because it is a chronic condition. The pigment-producing cells in people with melasma tend to be sensitive to triggers, and as long as triggers remain, especially sunlight and hormones, the pigment can come back and darken. Melasma care is therefore viewed as long-term control rather than a one-time fix.

Practical ways to prevent melasma from recurring or darkening include:

• Choose a broad-spectrum sunscreen of SPF 30 or higher (many people choose SPF 50), apply it in a generous amount every day, and reapply through the day when outdoors for long periods.
• For people with melasma, there is evidence that tinted sunscreen, which helps protect against visible light, may help with melasma better than regular sunscreen in some studies, making it worth considering.
• Add physical protection such as wide-brimmed hats, umbrellas, and sunglasses.
• Avoid accumulated heat on the face as much as possible, and care for your skin gently without harsh scrubbing.
• Keep up care and follow-up with a doctor, and do not stop abruptly the moment melasma starts to fade, because stopping care is a common reason it comes back.

Consult a Doctor for an Individualized Plan

Melasma has many causes and several types, so an accurate diagnosis by a doctor is the starting point of targeted care. If you want to know which type of melasma you have and how to care for it in a way that suits your own skin, you can consult the Onnyx Clinic medical team for an assessment and an individual treatment plan, including pigment care with Pico Laser. Results vary by individual.

To book an appointment or ask for more information, contact us via LINE: @onnyxclinic

References

• American Academy of Dermatology (AAD): Melasma — Causes — aad.org
• American Academy of Dermatology (AAD): Melasma — Diagnosis and treatment — aad.org
• DermNet: Melasma — dermnetnz.org
• Melasma. StatPearls (NCBI Bookshelf) — ncbi.nlm.nih.gov
• Melasma: the need for tailored photoprotection to improve clinical outcomes — PMC (NIH) — pmc.ncbi.nlm.nih.gov