Tried and true: Properly used, chemical peels provide dependable results

Sewickley, Pa. - Chemical peels can be used safely and effectively for a broad range of indications and in patients of all skin types, but achieving success depends on proper skin preparation and matching the peel depth to the indication, says Suzan Obagi, M.D., director of the UPMC Cosmetic Surgery & Skin Health Center, Sewickley, Pa., and assistant professor of dermatology, University of Pittsburgh, Pittsburgh.

"With the emergence of lasers for skin rejuvenation, chemical peeling has taken a back seat. However, the rapid introduction of new lasers provides testament to the fact that this technology has many limitations in terms of the results that can be achieved" Dr. Obagi says.

"In many situations, chemical peeling offers the opportunity to achieve comparable or superior results. While concern about complications and lack of control of peeling depth has also contributed to declining interest in chemical peels, these issues can be easily addressed with an emphasis on proper patient selection and preparation," Dr. Obagi says.

Preparation

Patients who are undergoing chemical peels should begin their skin preparation regimen six to 12 weeks prior to the procedure. Designed to enhance the response to the peel and prevent complications, the strategy incorporates a topical retinoid, alpha-hydroxy acid, hydroquinone, and a physical sunblock containing zinc oxide or titanium dioxide.

Dr. Obagi says she begins all patients on once nightly topical tretinoin and prescribes either a 0.05 percent or 0.1 percent formulation, depending on skin thickness. Pretreatment with the retinoid facilitates postpeel re-epithelialization and increases new collagen production in response to the peel.

A 6 percent alpha-hydroxy acid lotion is used daily in all patients with oily skin in order to enhance penetration of the other topical agents and the chemical peeling solution.

Hydroquinone 4 percent twice daily is prescribed for all patients except those with Fitzpatrick skin type I as a means to prevent postinflammatory hyperpigmentation (PIH) after the chemical peel.

"Fear of inducing pigmentary changes has been a major reason why clinicians have avoided chemical peels in darker skin patients. However, with proper preparation, it is possible to safely peel patients with any skin type who walk through your door," Dr. Obagi says.

Treatments

Patients with mild photodamage or textural roughness are candidates for treatment with a series of light exfoliative peels using 30 percent salicylic acid, 20 percent to 70 percent glycolic acid, or Jessner’s solution.

Improving the appearance of fine lines, enlarged pores, stretchable acne scars (valley shaped), and more moderately advanced sun damage requires a peeling agent that penetrates to the papillary dermis where it can stimulate fibroblast response and skin tightening.

Options include varying concentrations of trichloroacetic acid (TCA).

Dr. Obagi prefers to use 20 percent to 25 percent TCA mixed with a Blue Peel (Obagi Medical) base applied in multiple coats until the correct depth of penetration is reached.

Treatment of deeper lines and boxcar acne scarring require deeper peels targeting the upper reticular dermis. Use of the newer modified phenol solution or a deeper application of TCA allows these procedures to be done safely and effectively, but caution is still needed.

"Deep chemical peeling is a procedure that should be undertaken only after one has become very adept and comfortable with medium depth peels. However, when deep peels are performed correctly by experienced hands, the results that can be achieved are far superior to those associated with the use of noninvasive lasers," Dr. Obagi says.

Postop care

Postpeel care involves continuation of the pretreatment topical regimen once reepithelialization is complete combined with close follow-up to enable early detection of complications and prompt intervention. In particular, patients should be monitored for signs of infection, contact dermatitis, and incipient scarring, Dr. Obagi says.

If infection occurs, the likely pathogen may be predicted by the interval to onset of signs and symptoms. An infection that develops within the first few days is most often caused by Staphyloccocus, while yeast may be suspected when the onset is between five and seven days postpeel, and viral infection reactivation tends to manifest two to 10 days after the procedure.

"In any case, a specimen should be obtained to perform a KOH prep to detect yeast and for cultures for viral and bacterial pathogens," Dr. Obagi says.

Allergic contact dermatitis should be considered in patients whose postop course is proceeding well but changes suddenly, with the development of irritation, itching and regression of wound healing.

Propylene glycol found in emollient preparations is a common culprit for an allergic reaction, but patients should be instructed to discontinue all existing topical products and begin using water only for cleansing and topical application of petrolatum and a mid-potency topical corticosteroid.

"It is important to both remove the inciting cause and control existing inflammation that is a precursor to PIH and scarring,” Dr. Obagi says.

If healing is proceeding poorly by day 10 after the peel and significant erythema is still present, patients need to be monitored closely for incipient scarring through weekly follow-up visits.

Interventions to consider include low fluence pulsed-dye laser treatment and a topical corticosteroid to prevent scar maturation.

With the objective of reeducating colleagues about the utility of chemical peels, Dr. Obagi encouraged them to assume an active role in patient counseling.

"Our patients are coming to our offices requesting specific procedures and then spending a lot of money to achieve what are often modest results. While their initiative to research alternatives should be acknowledged, in the end, it is the physician, not the patient, who should be guiding the treatment decision," Dr. Obagi says. DT

Disclosure: Dr. Obagi reports no relevant financial interests.