Chemical peeling is an applied procedure which creates controlled destruction of all layers of the epidermis or dermis, subsequently causes exfoliation followed by regeneration of layers with the final result of improved texture and appearance of the skin. Various indications of chemical peeling actions include damage to skin structure (skin aging, scars, pigmentation disorders), superficial tumors (seborrheic keratosis, lentigo, actinic keratosis), and inflammation such as acne vulgaris. Various chemicals commonly used for procedures in peeling include alpha hydroxy acid or alpha-hydroxy acids (AHA) such as Glycolic Acid (GA) 20-70%, lactic acid, malic acid, pyruvic acid; beta hydroxy acids / BHA (10-30% salicylic acid), carbon dioxide snow, Jessner solution, lipohydroxy acid, resorcinol, retinoic acid, trichloroacetic acid (TCA), phenols, Baker - Gordon formula. In this study, the investigators are using glycolic acid 35% solution. Based on its mechanism of action, glycolic acid (GA) is a keratolytic agents, in which it penetrates the stratum corneum and interfere with corneocyte adhesion by damaging the intercellular desmosome bonds. Until now, GA is a superficial peeling that is very popular and most widely used throughout the world .

The advantages of GA peeling include odorless, colorless, painless, permanently effective, and minimal side effects. However, unlike non-AHA peeling materials, peels made from AHA cannot be neutralized by themselves. Without neutralization, AHA will penetrate deeper and may cause scars. Neutralization is the process of applying a base solution to stop the work of chemicals in peeling. In neutralization, liquids that can be used are alkaline liquids such as water, sodium bicarbonate, sodium hydroxide or ammonium saline solution to stop its work. In various literature, it is stated that water can be used as a neutralizing liquid in the chemical peels of AHA. It has also been mentioned in the literature that neutralization with sodium bicarbonate on the market does not provide any advantage over water use, as long as the acid is completely removed from the skin surface. The objective of this research is to look into the effectiveness, safety , and cost efficacy of water (H2O).

Inclusion Criteria:

1. 18-60 years old, male or female,
2. Patients who visited the outpatient department of Cosmetic Dermatology Division in RSCM with almost symmetrical lesions and will undergo chemical peeling procedure using 35% glycolic acid solution
3. Patients who have received priming with minimal priming ingredients containing topical retinoic acid with a concentration of 0.025%; 0.05%; 0.1% for at least 2 weeks and has been discontinued for 1 - 3 days before chemical peeling procedure.
4. Patients who are willing to be the subject of research by signing a research consent letter after being given an explanation (informed consent)

Exclusion Criteria:

1. Pregnancy, breastfeeding at the time of examination.
2. A history of systemic illness or in therapy for hormonal / endocrine disorders or other serious illnesses and / or in immunosuppressant therapy.
3. History of skin abnormalities due to photosensitivity, or allergic / severe complaints of side effects of drugs when priming.
4. History of atopy.
5. Difficulty in compliance following treatment

The participant and outcomes assessor will be masked in regards to which part of the face that the participant will receive water/sodium bicarbonate as neutralizing agent after chemical peeling