Melasma: Why It Happens and Why It Keeps Coming Back

Melasma is one of the most common—and often one of the most persistent—pigment concerns seen in dermatology and aesthetic medicine. It typically appears as patchy brown or grey-brown discolouration on areas such as the cheeks, forehead, upper lip, and chin. In some people, pigmentation may also appear on the neck or forearms.

Although melasma is harmless, its chronic and recurring nature can be frustrating and may affect confidence and quality of life. So why does melasma keep coming back? The answer is that melasma usually isn't caused by one single factor. Instead, it develops through a combination of genetics, hormones, sun exposure, visible light, heat, inflammation, skin irritation, and other individual triggers.

Understanding these triggers is an important first step toward managing melasma successfully over the long term.

1. Skin Type and Ethnic Background

Melasma is especially common in people with Fitzpatrick skin types III–V, including many Asian, Latin American, Middle Eastern, Black, and Indigenous populations. These skin types generally have more active pigment-producing responses. This means melanocytes—the cells responsible for producing melanin—may react more strongly to:

• UV exposure

• Visible light

• Heat

• Hormonal changes

• Skin irritation and inflammation

As a result, even relatively minor triggers can sometimes cause noticeable pigmentation.

2. Genetics

Melasma often runs in families. A significant number of people with melasma report having relatives who experience similar pigmentation. Genetics may influence how sensitive melanocytes are to environmental and hormonal triggers. If melasma runs in your family, your skin may simply have a lower threshold for developing pigmentation.

3. Hormonal Changes

Hormones are another important factor in melasma.

Pregnancy

Melasma during pregnancy is sometimes called chloasma or the “mask of pregnancy.” Changes in estrogen, progesterone, and melanocyte-stimulating hormones can increase pigment production, making melasma more likely to appear or become darker.

Birth Control & Hormone Therapy

Oral contraceptives and certain forms of hormone therapy may also trigger or worsen melasma in susceptible individuals.

Hormonal Changes Over Time

Melasma may improve after pregnancy or after hormonal medications are discontinued, but this does not always happen. Once pigment-producing pathways become highly reactive, the skin may continue to respond strongly to sunlight, heat, and inflammation even after the original hormonal trigger has changed.

4. Sun Exposure: One of the Biggest Triggers

Sun exposure is one of the most important external factors affecting melasma. UV radiation stimulates melanocytes and can increase inflammatory activity within the skin, encouraging additional pigment production.

Importantly, exposure doesn't have to mean spending hours outdoors. Regular incidental exposure can also contribute to melasma recurrence. This is one reason melasma commonly becomes more noticeable during the summer and may fade somewhat during the winter. Daily sun protection is therefore essential—not only while treating melasma, but also for maintaining results.

5. Visible Light and Heat

UV isn't the only environmental trigger. Research increasingly suggests that visible light, including high-energy visible light, can contribute to pigmentation in melasma-prone skin. For this reason, tinted sunscreens containing iron oxides may provide additional protection against visible light compared with conventional UV protection alone.

Heat may also contribute to melasma in some individuals by influencing vascular and inflammatory pathways. Potential heat exposure can include:

• Saunas and steam rooms

• Hot yoga

• Prolonged cooking near high heat

• Hot environments and climates

For someone whose melasma repeatedly flares despite good sun protection, heat exposure may be worth considering as part of the overall picture.

6. Age and Cumulative Exposure

Melasma frequently develops during adulthood, particularly during the reproductive years. Over time, cumulative sun exposure, hormonal changes, inflammation, and changes in the skin barrier can all influence pigmentation. This is one reason melasma should be viewed as a condition that may require ongoing management rather than a problem that can always be permanently removed with a single treatment.

7. When Cosmetic Treatments Can Make Melasma Worse

One of the biggest challenges with melasma is that the skin can be highly reactive to inflammation.

Aggressive treatments may sometimes create additional inflammation and lead to post-inflammatory hyperpigmentation (PIH), potentially making pigmentation appear darker. Extra caution may be needed with treatments such as:

• Aggressive chemical peels

• Ablative laser treatments

• High-fluence energy treatments

• IPL, particularly in darker or highly reactive skin types

• Deep or overly frequent microneedling

This does not necessarily mean that people with melasma cannot receive aesthetic treatments. Instead, treatments should be carefully selected and customized according to skin type, pigmentation depth, sensitivity, and individual triggers. With melasma, stronger treatment does not automatically mean better results.

8. Overly Aggressive Skincare

Sometimes the problem isn't a procedure—it's the everyday skincare routine. Overusing active ingredients can disrupt the skin barrier and create ongoing irritation. Common examples include excessive use of:

• Retinoids

• AHAs and BHAs

• Physical scrubs

• Strong exfoliating products

• Fragranced or irritating products

• Multiple active ingredients at the same time

  
  

For melasma-prone skin, maintaining a healthy, calm and well-hydrated skin barrier is an important part of pigmentation management.

9. Medications and Photosensitivity

Certain medications can increase sensitivity to sunlight or influence pigmentation. Depending on the individual medication, these may include some:

• Antibiotics

• Anti-seizure medications

• Diuretics

• Anti-inflammatory medications

• Retinoids

• Hormonal medications

If pigmentation suddenly develops or becomes noticeably worse after starting a medication, discuss it with your physician or pharmacist. Do not stop a prescribed medication without speaking with your healthcare provider.

10. Thyroid and Other Medical Factors

Some research has found an association between melasma and thyroid disorders, although the exact relationship remains unclear. Hormonal, metabolic, genetic, and environmental factors may interact differently from person to person. If melasma appears alongside other unexplained symptoms or significant hormonal changes, a medical assessment may sometimes be appropriate.

Why Does Melasma Keep Coming Back?

This is perhaps the most important thing to understand about melasma: Removing visible pigment does not necessarily remove the tendency to produce pigment. Even after the skin looks clearer, melanocytes may remain highly responsive to UV exposure, visible light, hormones, heat, and inflammation. This is why pigmentation may return after initially successful treatment—especially after summer, travel, hormonal changes, skin irritation, or excessive treatment.

Managing Melasma Is a Long-Term Strategy

Melasma is generally better approached as a chronic, relapsing pigment condition rather than a temporary cosmetic concern. Successful management often involves a combination of:

• Consistent daily photoprotection

• Protection against visible light when appropriate

• A gentle, barrier-supportive skincare routine

• Identifying personal triggers

• Carefully selected pigmentation treatments

• Avoiding unnecessary inflammation

• Ongoing maintenance after improvement

The treatment plan should also be individualized. What works well for one person's melasma may not be appropriate for another person's skin type or pigmentation pattern.

The Bottom Line

Melasma can be stubborn, but it can often be managed and significantly improved. The goal isn't simply to remove as much pigment as possible as quickly as possible. The goal is to calm pigment activity, improve existing discoloration, protect the skin from triggers, and reduce future flare-ups.

Patience and consistency matter.

At Reviva Laser Skin Clinic, we assess each patient's skin type, pigmentation pattern, sensitivity, and treatment history before recommending an individualized approach to melasma management.

If you're struggling with recurring pigmentation or melasma that keeps returning after treatment, a professional skin assessment can help determine which factors may be contributing and which treatment approach may be most appropriate for your skin.

Reviva Laser Skin Clinic150B – 8220 Lansdowne Road, Richmond, BC604-233-0878