Résumé de communication

Objectives: Peeling agents showing improvements in different dermatologic and aesthetic concerns have made chemical peels a very versatile procedure. Different molecules have unique mechanisms of actions and combining them in different ways can offer a synergistic effect on the primary condition. Sequential peel is a technique in which peels are applied in sequence. The first peel is applied, and its action is terminated after a specific amount of time. This is followed by the application of another peeling agent which can be left on as a leave on peel or may be neutralized after a certain amount of time Introduction: The first peel enhances the penetration of the second peeling agent by causing a controlled exfoliation resulting in a greater peel depth. Different peeling agents have different acidity (pKa) and combining them in a single formulation may not be pharmacologically compatible and may disturb their individual efficacy. Hence two peels are applied one after another in order to achieve the optimal result of both the peeling agents. Sequential peeling is effective in acne, acne with post inflammatory hyperpigmentation, scars, photoaging, tanning, melasma, lichen planus pigmentosus Materials / method: A study conducted on sequential peeling (Mahmoud et al) for acne concluded that sequential peeling with glycolic acid (GA) and salicylic acid (SA) was equally effective in reducing lesion count, disease grading and IL levels in comparison with doxycycline alone or in combination with the same peeling regimen. SA 30 % peel followed by GA 35-70% peel is an effective treatment modality for acne with post inflammatory hyperpigmentation (PIH) as well as pustular acne. SA30 % peel may be followed by lactic acid (LA) 80% peel for the improvement of acne excorie. Results: For melasma, sequential peeling with TCA 15% followed by modified Jessner’s solution has been tried by previous authors. Modified Jessner's solution improved results along with TCA in melasma and proved to be a useful adjuvant. Several combination peels containing TCA and phenol can be used following application of GA 20-35% in facial melasma. Combination peels containing glycolic kojic acid (33 % GA and 7% kojic acid) followed in sequence with the application of a combination peel containing TCA and tranexamic acid (TXA) may also be tried to improve pigmentation. Conclusion: Periorbital Melanosis also responds well to sequential peeling. In a previous study LA 15% in combination with TCA 3.75 % has been used in periorbital hyperpigmentation. Arginic acid peels can be followed in sequence by combination peels containing mandelic acid and thioglycolic acid with the aim of improving the hemosiderotic pigmentation in dark circles. Keratosis pilaris (KP) is also an indication for using sequential peels. A SA 30% or GA 70% chemical peel may be followed sequentially by a leave on tretinoin peel in order to improve the pigmentation and follicular prominence