Vitamin A and retinoids

    Of the vitamin A peeling products, the most effective are the vitamin A acids tretinoin (all-trans-retinic acid) and isotretinoin (13-cis-retinic acid). Vitamin A acid works by increasing the rate of division of the basal cells, i.e. in thickening of the epidermis (the outer cells of the skin). The horny layer is reduced, the thickness of the epidermis increased, and the formation of collagen stimulated. Under the influence of vitamin A acid, the skin appears smoother and tauter, and the number and depth of small wrinkles and lines is reduced. The skin’s surface presents a more even appearance as horny blemishes and pigmentation disturbances are reduced. The local concentrations of treninoin used are between 0.01 and 0.1 %, with 0.05 to 0.1 % being the most frequent. The tretinoin is applied to the facial skin in the evening in the form or a cream or gel. After 8 to 12 months, application should be reduced to 2 or 3 times a week and can then be continued indefinitely. Because of the peeling and drying effect, moisturising creams should be applied in the morning. Sun protection products should also be used. In many cases, smoothing of lines and wrinkles does not become apparent for several months. As side effects, vitamin A acids can cause transitory dryness and redness of the skin, and in very rare occurrences also blistering. However, these side effects are of a local nature only. The dryness and redness are seen as the effects of the treatment. If the side effects are severe, the application on dry skin should be reduced to once or twice a week. If this is found to be tolerated well, the frequency can then be increased again. It is advisable to use UV filters during the daytime as vitamin A is inactivated by UV radiation.

    Superficial peelings should never be used on the eyelids. The skin of the eyelids is very sensitive and can easily become irritated.

    Fruit acids

    Chemically speaking, fruit acids are alpha-hydroxy acids and are also known by their abbreviation of AHAs. Fruit acids are contained in natural products and include such things as glycol acid, tartaric acid, citric acid, malic acid and lactic acid. AHAs release the protein connections of the dead cells on the skin’s surface. The horny layer is loosened and the individual horny scales are shed, allowing the “fresh” cells to appear. The skin appears smoother and more even. Small lines and wrinkles disappear after a few weeks. The fruit acids cause the rate of division of the basal cells to increase. Fruit acids are also good at retaining moisture. Concentrations of 6 – 12 %, or in some cases even higher, are used in the form of creams with a low pH value of 4. They can be applied daily, or in lower concentrations even twice daily, over a period of at least 2 to 3 months. Once a noticeable improvement has occurred, application can often be reduced to only 2 or 3 times a week. Fruit acids are sometimes used by dermatologists in concentrations of as high as 40 or even 70 %.

    The treatment with superficial peelings causes the horny layer to become thinner. However, a thinner skin also reduces the skin’s natural protection against sunlight. People using superficial peelings should therefore be informed of the increased sensitivity to sunlight, and are strongly advised to apply sun protection creams.

    The most effective and, aside from cosmetic operations, the most invasive form of cosmetic treatment are medium-depth and deep peelings. In this case, chemicals are used to treat the epidermis (outer skin), and the underlying layer, the dermis. This method can be applied to deal with small or bigger wrinkles, hornification and pigment blemishes in the face. The most commonly used chemicals for this kind of peeling are phenol and trichloroacetic acid.


    Phenol has been in use for more than 20 years as a standard procedure for chemical peeling treatment. Especially the Baker-Gordon solution has become firmly established, peeling the skin down to the upper dermis layer and allowing the treatment of medium wrinkles, light damage, superficial skin tumours, and pigment blemishes such as melasmae, freckles and lentigo. Phenol works by causing controlled chemical damage to the skin and upper dermis layer. During the healing process, the epidermis is renewed, with the formation of new collagen. The epidermis recovers fully within about 7 days from application. However, the skin is subsequently highly sensitive to light, so that direct exposure to the sun must be absolutely avoided for a period of 6 months. Additionally, UVA and UVB filters should be used for life.

    Phenol treatment must in no circumstances be used on the upper eyelids, right up to the area below the eyebrows. In treatment of the facial skin, there is only little risk of scarring. Because of the large number of hair follicles and sebaceous glands, reepithelialisation (recovery of the skin layer) is encouraged. Treatment of this kind on areas of skin other than the face involves a higher risk of scar formation. Another risk is that of hyperpigmentation or noticeable pigment contrasts at the borderline between the areas of treated and untreated skin. As men’s skin is thicker, it tends to be less suited for peeling treatment than that of women.

    Trichloroacetic acid

    The methods of peeling treatment using trichloroacetic acid (TCA) are more controllable and less aggressive than those using phenol. For superficial peeling, a 10 to 25 % solution is used, for medium-depth peeling a 30 to 35 % solution, and for deep peeling a 50 to 60 % solution. Deep peeling using TCA produces almost the same results as with phenol peeling. Because of the better controllability, it can also be used for treating the areas of skin outside of the face. TCA also has a less strong bleaching effect on melanin, the skin pigment. Because it is less aggressive. however, TCA is not able to treat deeper folds of skin. TCA also results in less production of new collagen by the dermis. Before undergoing peeling with TCA, it is recommended to use a milder peeling for a period of 4 to 6 weeks with a cream containing 0.1 % tretinoin and 4 % hydrochinon. Salicylic acid or alpha-hydroxy acids can also be used as the peeling agents.

    Both after superficial to medium-depth and medium-depth to deep peeling treatment, complete sun protection is essential for many months. Subsequently, high-filter UVA and UVB sun protection agents should be used for the rest of one’s life. As follow-up treatment, the use of tretinoin-hydrochinon cream appears recommendable for a period of 4 weeks. In the case of deep peelings, a 2 to 3 month pause must be observed before undergoing renewed treatment.

    Dr. Obagi’s Blue Peel

    The method used by the US physician Dr. Obagi is based on peeling with trichloroacetic acid in combination with a blue tincture which, in addition to a food dye, also contains saponin, a substance obtained from the yucca palm. This method is popular because it can evidently be more safely controlled than conventional peelings, and also appears to have fewer side effects. According to reports, the patients feel only a slight burning sensation while undergoing treatment. The subsequent healing process is also usually gentler, faster and less complicated. On the 2nd to 10th day after application of the peeling – depending on the concentration and depth of treatment – redness, swelling, peeling and also scabbing of the skin occurs. Sun protection products with a light protection factor of 30 and more must be used for up to 6 weeks in order to avoid unwanted pigmentation.


    Peeling for light-aged skin can also be performed by spraying on liquid nitrogen. The effect of this treatment is likely to be the same as that for surface or medium-depth treatment using TCA. Cryo-therapy is, however, not yet a standard procedure.