Combination Salicylic Acid TCA Chemical Peeling

The author has no financial interest in any of the products or equipment mentioned in this chapter. 

In 2002, Grimes reported the efficacy of combination salicylic acid/TCA 10% peeling [1]. She treated patients with moderate to severe melasma with this combination regimen. In the series, nine patients were classified as Fitzpatrick skin type IV, eleven were skin type V, and seven were skin type VI. Many of the subjects included in the study had not responded to salicylic acid or glycolic acid peels. The concentration of salicylic acid was 20 and 30%, and the TCA concentration was 10%. A series of four peels was performed at 2-week intervals. Thirty percent of the patients experienced moderate improve- 

Salicylic acid (ortho hydroxybenzoic add) is a beta hydroxy acid agent. It is a lipophilic compound which produces desquamation of the stratum corneum via removal of intercellular lipids [3] (see salicylic acid section). Given its keratolytic effects, it has become an increasingly popular superficial peeling agent. Salicylic acid peels induce injury via thinning or removal of the stratum corneum. In addition, salicylic acid potentially enhances the penetration of TCA. 

Trichloroacetic Acid (TCA) causes precipitation of proteins and coagulative necrosis of epidermal cells [4]. The extent of damage is indeed concentration dependent. Concentrations range from 10 to 50%. Superficial TCA peeling is induced by concentrations of 10-30% whereas higher concentrations cause medium depth or deep peeling. The combination of salicylic acid followed by TCA 10-15% induces superficial wounding. 

Ethanol formulations of salicylic acid (20 and 30%) are used for combination peeling (see salicylic acid section). Trichloroacetic acid is prepared as an aqueous solution, since ethanol solutions do not penetrate the skin. It is prepared by mixing the appropriate concentration of crystals with up to 100 cc of distilled water. Ten and fifteen percent TCA is prepared by mixing 10 or 15 g of crystals in up to 100 cc of total volume, respectively. Aqueous solutions of TCA remain stable for up to 6 months unless contaminated. Other methods have been used to formulate TCA peeling solutions however, the weight/volume methods appear to be the most reliable formulation [5]. Premixed TCA solutions are available from a variety of medical 

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Combination Salicylic Acid/TCA Chemical Peeling Chapter 10... 

Combination Salicylic Acid/ TCA Chemical Peeling Pearl E. Grimes... 

We usually utilize bio-revitalization before combined peeling with 25% salicylic acid followed by 25% TCA in patients with photoaging of the face, hands, neck, or decolt6 who complain of skin dryness and hyperpigmentation. Combining the two procedures enhances results of treatments as bio-revitalization improves skin brightness and moisturization and chemical peeling improves skin texture and color (Fig. 10.1a, b, c). 

In patients with Fitzpatrick skin types IV to VI, the use of salicylic acid as a very light chemical peeling agent seems to result in a much lower incidence of PIH Combination peels have replaced 50% TCA as the gold standard for medium-depth peels... 

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