Chemical Peels in Pigmentary Disorders: Comparative Efficacy of Glycolic, Salicylic, and TCA Peels

Henry Elijah Department of Dermatology and Dermatological Oncology^*
*Correspondence: Medical University of Lodz, 90-419 Lodz,. Henry Elijah, Department of Dermatology and Dermatological Oncology, Poland, Email:

Introduction

Pigmentary disorders such as melasma, Post-Inflammatory Hyperpigmentation (PIH) and lentigines are among the most common dermatologic complaints, especially in individuals with darker skin types. These conditions pose therapeutic challenges due to their chronic nature, risk of recurrence and the need for treatments that are both effective and safe across a range of Fitzpatrick skin types. Chemical peels have long served as a cornerstone in the management of pigmentary disorders due to their ability to accelerate epidermal turnover, disrupt melanin synthesis and enhance the penetration of topical agents. Among the various chemical peeling agents, glycolic acid, salicylic acid and TriChloroacetic Acid (TCA) have gained significant clinical utility. Each agent differs in terms of its depth of penetration, mechanism of action, tolerability and overall efficacy. A comparative assessment of these peels provides valuable insight for clinicians aiming to tailor treatment strategies based on patient needs and skin type. Glycolic acid, an Alpha-Hydroxy Acid (AHA), is widely used for superficial chemical peels. Derived from sugarcane, its small molecular size allows for effective epidermal penetration, promoting desquamation and increased cell turnover. Glycolic acid also exhibits humectant properties, which enhance skin hydration and tolerance. In pigmentary disorders, glycolic acid peels work by reducing corneocyte cohesion, stimulating fibroblast activity and dispersing melanin aggregates in the epidermis. Concentrations typically range from 20% to 70%, with higher concentrations used for more resistant hyperpigmentation. Multiple studies have confirmed the efficacy of glycolic acid peels in melasma, with visible improvement noted after 4â??6 sessions spaced at two- to three-week intervals. The peelâ??s exfoliative effect also facilitates the penetration of adjunctive agents such as hydroquinone and retinoids, enhancing overall pigmentary clearance. However, in darker skin types, care must be taken to avoid excessive irritation or post-peel inflammation, which may paradoxically worsen hyperpigmentation if not carefully monitored [1].

Description

Salicylic acid, A Beta-Hydroxy Acid (BHA), is lipophilic and particularly effective in treating pigmentary disorders associated with acne and seborrhea. It penetrates the pilosebaceous units and exerts comedolytic, anti-inflammatory and keratolytic effects. These properties make salicylic acid an ideal agent for patients with concurrent acne and post-acne pigmentation. Typically used in concentrations of 20% to 30%, salicylic acid peels produce a characteristic white frost or pseudofrost due to protein coagulation. Repeated application leads to progressive lightening of hyperpigmented macules, especially those with epidermal pigment. Salicylic acidâ??s anti-inflammatory action reduces the risk of PIH, making it suitable for sensitive or reactive skin types. Comparative studies have shown that salicylic acid peels are particularly effective in managing acne-induced hyperpigmentation and in some cases, may be better tolerated than glycolic acid peels, especially in Fitzpatrick skin types IVâ??VI. One of the advantages of salicylic acid is the minimal downtime and the reduced likelihood of visible peeling, which appeals to patients seeking subtle, no-downtime treatments.

TriChloroacetic Acid (TCA) is a deeper-penetrating agent that can be used for medium to deep peels depending on the concentration. TCA induces protein coagulation and tissue necrosis, followed by epidermal regeneration and dermal remodeling. Lower concentrations (10-20%) are used for superficial peeling, while higher concentrations (30-50%) are reserved for more aggressive treatment of actinic damage, lentigines and dermal melasma. TCA peels are particularly effective for treating stubborn pigmentary conditions such as lichen planus pigmentosus or mixed-type melasma. They stimulate neocollagenesis and improve overall skin texture and tone. However, TCA peels are associated with more intense post-peel erythema, crusting and potential complications including scarring and PIH, particularly in darker skin tones. Therefore, careful patient selection, pre-peel priming and strict post-peel care are critical. In many cases, combination approaches using TCA spot peeling or blending with agents like Jessnerâ??s solution can offer a safer, more controlled depth of exfoliation [2].

Conclusion

Chemical peels remain a versatile and effective option in the treatment of pigmentary disorders. Glycolic acid, salicylic acid and TCA peels each offer unique benefits and limitations that must be carefully matched to the individual patientâ??s condition and skin type. Glycolic acid is preferred for superficial pigmentation and photodamaged skin, salicylic acid for acne-associated pigmentation and darker skin types and TCA for deeper or more resistant pigmentary lesions. A personalized, evidence-based approach that considers skin biology, pigmentation depth and patient expectations is essential for optimal outcomes. With appropriate selection, technique and maintenance, chemical peels can significantly improve skin tone, texture and confidence in patients affected by pigmentary disorders.

Acknowledgement

None.

Conflict of Interest

None.

References

1. Tomic, Dunya, Jonathan E. Shaw and Dianna J. Magliano. "The burden and risks of emerging complications of diabetes mellitus." Nat Rev Endocrinol18 (2022): 525-539

              Google Scholar Cross Ref Indexed at

2. Johnpulle, Romany AN, Douglas B. Johnson and Jeffrey A. Sosman. "Molecular targeted therapy approaches for BRAF wild-type melanoma." Curr Oncol Rep18 (2016): 1-8.