Melasma: Causes, Symptoms, Diagnosis and Management

~Introduction

Melasma is a common acquired pigmentary disorder of the skin that presents as symmetrical brown or gray-brown patches, primarily on sun-exposed areas of the face. Although harmless in terms of physical health, it often carries a heavy emotional and psychological burden due to its chronic, relapsing nature and its impact on appearance.

It is sometimes referred to as the “mask of pregnancy” when it occurs in pregnant women, but it also frequently affects non-pregnant women and, less commonly, men. The exact cause is multifactorial, involving genetics, hormones, and ultraviolet (UV) radiation, but the precise mechanisms remain under investigation.

This article provides a comprehensive overview of melasma, exploring its history, causes, epidemiology, pathogenesis, clinical features, diagnosis, treatment options, prevention strategies, and ongoing research.

~Historical Background

Melasma has been documented for centuries in various populations, especially in regions with strong sunlight exposure. Its name is derived from the Greek word melas, meaning “black,” reflecting the dark pigmentation characteristic of the condition. Historically, it was strongly associated with pregnancy and called chloasma gravidarum, or the “mask of pregnancy.”

Over time, dermatologists recognized that melasma can affect individuals outside of pregnancy and that hormonal influences, environmental factors, and genetics all play important roles. Today, melasma is one of the most common pigmentary conditions treated in dermatology clinics worldwide.

~Epidemiology

Prevalence: Melasma affects an estimated 1–33% of the population, depending on the demographic and geographical location.
Gender: Women are disproportionately affected, accounting for 90% or more of cases. Men, however, can also develop melasma, particularly in sun-exposed populations.
Ethnicity: It is more prevalent in individuals with darker skin types (Fitzpatrick types III–V), such as those of Hispanic, Asian, Middle Eastern, and African descent.
Age: Typically appears in reproductive years (20–50 years), though it can persist or develop later in life.

~Causes and Risk Factors

Melasma arises from an interplay of endogenous and exogenous factors.

1. Ultraviolet (UV) and Visible Light Exposure

The single most important factor in melasma development and recurrence.
UV radiation stimulates melanocytes to produce excess melanin.
Visible light, particularly blue light, can also worsen pigmentation.

2. Hormonal Influences

Pregnancy: Elevated estrogen and progesterone levels trigger melasma in many women.
Oral contraceptives and hormone replacement therapy: Strongly associated with melasma onset or worsening.
Thyroid disease: Some studies suggest a link between thyroid dysfunction and melasma.

3. Genetic Predisposition

Family history significantly increases the likelihood of developing melasma.

4. Medications and Cosmetics

Photosensitizing drugs (e.g., phenytoin, tetracyclines) can exacerbate melasma.
Certain cosmetics or fragrances may induce phototoxic reactions leading to pigmentation.

5. Other Contributing Factors

Stress and oxidative stress.
Chronic skin irritation.
Air pollution and environmental toxins.

~Pathogenesis

Melasma is a hypermelanosis disorder, but its underlying pathophysiology is complex and multifactorial:

Melanocyte Hyperactivity
- Increased number and activity of melanocytes.
- Excess melanin synthesis and transfer to keratinocytes.
Dermal Component
- Melanin deposition in the dermis.
- Presence of melanophages (melanin-containing macrophages).
Vascular Factors
- Increased dermal vascularization observed in melasma lesions.
- Suggests interaction between vascular and pigmentary systems.
Hormonal Influence
- Estrogen and progesterone upregulate melanogenesis.
- Enhanced expression of melanocyte-stimulating hormone (MSH).
Genetic and Epigenetic Factors
- Specific gene polymorphisms linked to melanin synthesis pathways.

~Clinical Features

Melasma typically presents as symmetrical, hyperpigmented macules and patches with irregular borders.

1. Common Sites

Face (most common):
- Cheeks
- Forehead
- Upper lip
- Chin
- Nose bridge
Extra-facial sites: Neck, forearms, chest (less frequent).

2. Patterns of Distribution

Centrofacial pattern: Forehead, cheeks, nose, upper lip, chin.
Malar pattern: Cheeks and nose.
Mandibular pattern: Jawline (often in older patients).

3. Color and Appearance

Brown, dark brown, or grayish patches.
Clear distinction from surrounding skin.
Symmetrical distribution is a hallmark feature.

4. Symptoms

Usually asymptomatic.
Patients mainly complain of cosmetic disfigurement, lowered self-esteem, and psychosocial distress.

~Diagnosis

Diagnosis of melasma is primarily clinical, but additional tools can help in assessment:

History and Physical Examination
- Onset, triggers (pregnancy, hormones, medications, sun exposure).
- Distribution and symmetry of lesions.
Wood’s Lamp Examination
Wood's Lamp Examination
- Helps differentiate between epidermal, dermal, and mixed melasma.
- Epidermal melasma enhances under Wood’s lamp (better prognosis).
- Dermal melasma shows little to no enhancement (more resistant to treatment).
Dermoscopy
- Reveals pigment networks, telangiectasia, and depth of pigmentation.
Histopathology (rarely needed)
- Confirms increased melanin in epidermis and/or dermis.

~Differential Diagnosis

Conditions that mimic melasma include:

Post-inflammatory hyperpigmentation (PIH).
Lichen planus pigmentosus.
Drug-induced hyperpigmentation.
Addison’s disease.
Photodermatoses.

~Management

Principles of Treatment

No single cure exists; management is long-term.
Aim is to lighten pigmentation, prevent worsening, and minimize recurrences.
Requires combination therapy and strict sun protection.

1. General Measures

Sun Protection (cornerstone of therapy):
- Broad-spectrum sunscreen (SPF ≥ 30, with UVA/UVB and visible light protection).
- Protective clothing, hats, and avoidance of peak sun exposure.
Discontinuation of triggering agents: Stopping oral contraceptives or photosensitizing medications if possible.

2. Topical Therapies

A. Hydroquinone (HQ)

Gold standard depigmenting agent.
Inhibits tyrosinase (enzyme in melanin synthesis).
Usually prescribed as 2–4% cream.
Side effects: Irritation, ochronosis (rare).

B. Triple Combination Creams

Hydroquinone + Tretinoin + Corticosteroid.
Highly effective for short-term treatment.
Long-term use requires caution due to side effects.

C. Other Topical Agents

Azelaic acid: Safe and effective, especially in pregnant women.
Kojic acid: Natural inhibitor of melanin synthesis.
Tranexamic acid (topical): Reduces vascular contribution to melasma.
Niacinamide, arbutin, licorice extract, cysteamine: Mild depigmenting effects.

3. Oral Treatments

Oral Tranexamic Acid: Promising results in resistant melasma. Acts by inhibiting plasminogen, reducing vascular and melanocyte activity.
Antioxidants (Vitamin C, Vitamin E, Polypodium leucotomos extract): Used as adjuvants.

4. Procedural Therapies

Chemical Peels: Glycolic acid, salicylic acid, trichloroacetic acid (TCA). Best for epidermal melasma.
Laser and Light-Based Therapies:
- Q-switched Nd:YAG laser, fractional lasers, intense pulsed light (IPL).
- Risk of post-inflammatory hyperpigmentation (PIH) especially in darker skin.
- Should be used cautiously, as relapse is common.
Microneedling with topical agents: Enhances penetration of depigmenting drugs.
Platelet-Rich Plasma (PRP): Experimental but shows potential benefits.

5. Supportive and Psychological Care

Melasma has a profound psychological impact.
Counseling, support groups, and addressing self-esteem issues are important parts of management.

~Complications

Recurrence: Very common, even after successful treatment.
Side effects from therapy:
- Hydroquinone-induced ochronosis.
- Skin irritation from topical retinoids or peels.
- PIH following aggressive procedures.
Psychological distress: Depression and anxiety in severe cases.

~Prognosis

Melasma is chronic and relapsing.
Epidermal melasma responds better to treatment compared to dermal or mixed types.
Complete cure is rare, but with appropriate long-term management, pigmentation can be significantly improved.
Lifelong sun protection remains essential.

~Prevention

Regular use of broad-spectrum sunscreens.
Avoidance of unnecessary hormonal therapies when possible.
Careful selection of cosmetics to avoid phototoxic reactions.
Early treatment of pigmentation to prevent deep dermal involvement.

~Recent Advances and Research

Novel Depigmenting Agents: Cysteamine cream, topical TXA, and topical antioxidants are being actively studied.
Gene Therapy and Molecular Targets: Research into melanogenesis pathways could open up targeted treatments.
Nanotechnology: Nanocarrier-based delivery of depigmenting agents may improve efficacy and reduce side effects.
Combination Therapies: Ongoing studies emphasize the superiority of multi-modality approaches.

~Conclusion

Melasma is a common but complex pigmentary disorder with significant psychosocial consequences. Its development is influenced by genetic predisposition, hormonal changes, sun exposure, and other environmental factors. While treatments exist—ranging from topical agents and oral medications to procedural interventions—no permanent cure is available, and recurrences are common.

The key to successful management lies in a multifactorial approach that combines sun protection, medical therapies, lifestyle modifications, and psychological support. Advances in research hold promise for more effective, targeted, and long-lasting treatments in the future.

For patients, understanding the chronic and relapsing nature of melasma is crucial to setting realistic expectations, while dermatologists continue to refine strategies to improve both clinical outcomes and quality of life.

Health Lines

Thursday, September 11, 2025