What is the workup for melasma (chloasma)?

From the Guidelines

The workup for melasma should begin with a thorough clinical examination, including Wood's lamp examination to determine the depth of pigmentation, and a detailed history focusing on potential triggers such as sun exposure, hormonal medications, pregnancy, and family history. No extensive laboratory testing is typically required for most cases of melasma, as it is primarily a clinical diagnosis. However, if there are concerns about hormonal influences, thyroid function tests may be considered 1. A detailed history should be obtained to identify potential triggers and risk factors. Skin biopsy is rarely necessary but may be performed in atypical cases to rule out other conditions. Photography documentation is recommended to monitor treatment progress.

Key Components of Melasma Workup

• Clinical examination with Wood's lamp
• Detailed history focusing on sun exposure, hormonal medications, pregnancy, and family history
• Thyroid function tests if hormonal influences are suspected
• Skin biopsy in atypical cases
• Photography documentation for treatment monitoring

The cornerstone of management includes strict sun protection with broad-spectrum SPF 30-50 sunscreen applied every 2-3 hours when outdoors, wide-brimmed hats, and sun-avoidance behaviors. First-line treatment typically involves topical agents containing hydroquinone 2-4% applied once or twice daily for 12-16 weeks, often combined with tretinoin 0.025-0.1%, and a mild corticosteroid (like fluocinolone acetonide 0.01%) in what's known as the Kligman formula or triple combination therapy. For resistant cases, chemical peels (such as glycolic acid 20-70%), microdermabrasion, or laser therapy may be considered as second-line treatments. Tranexamic acid (oral 250mg twice daily for 8-12 weeks or topical 3-5%) has shown promising results for resistant melasma. Patient education about the chronic, recurrent nature of melasma and the importance of consistent sun protection is essential for managing expectations and improving outcomes.

From the FDA Drug Label

HYDROQUINONE USP, 4% SKIN BLEACHING CREAM is indicated for the gradual bleaching of hyperpigmented skin conditions such as chloasma, melasma, freckles, senile lentigines, and other unwanted areas of melanin hyperpigmentation. The FDA drug label does not answer the question.

From the Research

Melasma Workup

• Melasma is a chronic skin condition characterized by the overproduction of melanin in areas exposed to ultraviolet radiation 2.
• The pathogenesis of melasma is complex, involving multiple pathologies, including photoaging, excessive melanogenesis, increased mast cells, vascularization, and basement membrane damage 2.
• Melasma treatment is long-term and complicated, with recurrence and resistance to treatment being common issues 2, 3, 4, 5.

Diagnosis and Treatment Approach

• The treatment plan for patients with melasma begins with the elimination of risk factors, strict protection against ultraviolet radiation, and the topical use of lightening agents 2.
• A multimodality treatment approach targeting both pigment production and elimination is necessary to achieve equilibrium and disease remission 5.
• Topical tyrosinase inhibitors, peels, and laser and light-based devices can be used to reduce pigment production and increase elimination 5.
• Maintenance treatments are often necessary due to the high recurrence rate of melasma 5.

Treatment Options

• Topical agents, including hydroquinone, tretinoin, glucocorticosteroids, and various formulations, have been traditionally used to treat melasma 2, 3, 4.
• Other treatment options include chemical peels, laser and light treatments, mesotherapy, microneedling, and systemic therapy 2, 3, 4.
• Oral tranexamic acid, Polypodium leucotomos, and glutathione have shown promise as oral therapies for melasma 3, 4.
• Combination therapies within or across treatment modalities generally result in better efficacies than monotherapies 4.

Considerations for Patients with Skin of Color

• Melasma is more prevalent in skin of color, and ensuring the right approach for these patients is important to avoid adverse side effects 6.
• A flexible and focused treatment algorithm that reflects both treatment and maintenance periods is recommended for patients with skin of color 6.
• Dermatologists should consider the individual needs and skin type of their patients when selecting a treatment approach for melasma 6.