Glycolic acid peeling preparation

Long-term preparation starts 4—6 weeks before a water-based AHA peel, ft can be non-specific or specific, ft is not essential, but noticeably improves results by ensuring deeper and more even penetration of the glycolic acid peel. Greater vigilance is required when applying the peel, however, as it must be neutralized more quickly. 

If we leave aside these variables, we can fit the dilferent types of peels into their appropriate slots. This is just for the beauty of the exercise however, as the variables stiU need to be taken into account. It is clearly possible to perform a superficial or medium peel using phenol. But, given the inherent toxicity of phenol, what would be the point What is more, 70% unbuffered glycolic acid that is left for 10-15 minutes on a thin, sensitive skin that has been prepared with retinoic acid can result in a cosmetic disaster. It is possible to carry out good-quality, deep peels with TCA, but the risks can be greater than if phenol is used correctly. 

As a general rule, it is worthwhile preparing the skin carefully with tyrosinase inhibitors if there is any risk of post-peel pigmentary changes or to optimize results when treating melasma. Retinoic acid and sometimes glycolic acid are used to make transepidermal penetration more even or to deepen the action of the acid solution. 

AHAs are not toxic to melanocytes, and can therefore be applied on dark skins and in all seasons, on condition that effective sun protection is used. Contact time (Table 8.1) depends on skin type, peel concentration and formulation, its pH, the method of application, preliminary skin preparation, etc. At an identical pH, a 50% concentration of glycolic acid will penetrate half as deep as a 70% concentration, and will take twice as long to do so. 

With EPS, the AHAs penetrate far more evenly because of the type of vehicle used and the slow-release mechanism, which eliminates the need for pre-peel preparation. The different types of AHAs used in EPS are important the three AHAs in the solution actually penetrate at different speeds. Small molecules penetrate the skin more rapidly than larger molecules the glycolic acid is therefore the first to penetrate, followed by the lactic acid and finally the mandelic acid, the largest molecule, which relies on the lytic action of the other acids on the corneodesmosomes to help it penetrate the skin more easily. 

As in the superficial peel, medium-depth peel solution is compounded using a weight/volume method. A concentration of 35% should be prepared as described above (see Making up the solution). Combination peels are those using solid CO2 ice plus 35% TCA (Brody combination), Jessner s solution plus 35% TCA (Monheit combination), or 70% glycolic acid and 35% TCA (Coleman combination). These peels will be discussed in greater detail later. 

In an attempt to speed the penetration and depth of TCA peels, two modified peels were created which incorporate the use of a keratolytic agent. Monheit described a Jessner s-TCA peel utilizing a keratolytic acid preparation, Jessner s solution, applied prior to the application of TCA. Jessner s solution is comprised of 14% each of resorcinol, salicylic add, and lactic acid mixed in ethanol. Application of the Jessner s solution allows for faster and deeper penetration of the subsequently applied 35% TCA. A similar mechanism is employed with Coleman s glycolic acid-TCA peel, which uses 70% glycolic acid, also acting as a keratolytic, prior to application of 35% TCA. 

The patient consulted us regarding macular acne scarring. After preparation with sunscreens and 10% glycolic acid lotion at night for 2 weeks, she was treated with 30% salicylic acid peels once a month for 3 consecutive months. Figure 13.6 shows the remarkable improvement of skin texture and macular spots. 

Glycolic acid creams, cleansers, and exfoliating preparations are used to boost epidermal exfoliation, reduce stratum corneum thickness and augment the peel penetration, thus enhancing the uniformity of the light chemical peel. Pretreatment is also essential for combination medium-depth peels. 

They include defects in the mixing and storage of various agents. For glycolic acid, potency decreases with time check its expiration date. TCA should be measured weight by volume and stored in amber bottles where it lasts for about 6 months. TCA can become more potent with time. Baker s solution should be prepared fresh before the procedure is carried out. Carefully label all the bottles that contain peeling agents. Make sure they are not left in a place where a child can find and open them. 

Wang et al. (2002) demonstrated a composite membrane (subjected to PV) of an asymmetric poly(4-methyl-l-pentene) (TPX) membrane dip-coated with poly(acrylic acid) (PAA). To improve the interface peeling of the PA A/TPX composite membranes, the surfaces of TPX membranes were modified by residual air plasma in a tubular-type reactor. The plasma treatments were effective in rendering the asymmetric TPX membrane hydrophilic. Optimal results were obtained with PAA/TPX composite membrane prepared from the PAA/ethylene glycol (EG)/aluminum nitrate = 1/2/0.05 coating solution at 5 W/30 s plasma treatment condition. Concentration of the water in the permeate was nearly 100%, and a permeate flux of 960 g/m h was obtained with a 3 wt% feed acetic acid concentration. 

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