J. Cosmet. Sci., 72, 201–213 (March/April 2021) 201 Comparison of Urea-Based Compounding Moisturizers and Similar Commercial Products on Skin Barrier Function: A Randomized Biometric Study ANISEH SAMADI, ATEFEH NAEIMIFAR, SAMAN AHMAD NASROLLAHI, and ALIREZA FIROOZ , Center for Research & Training in Skin Diseases & Leprosy, Tehran University of Medical Sciences, Tehran, 1416613675 Iran Accepted for publication December 15, 2020. Synopsis Although several commercial moisturizers are available in the market, the continued role of pharmaceutical compounding has been still felt in dry skin management. This study aimed to evaluate the effect of a urea- based compounded moisturizer on barrier function, compared with a similar commercial product. Thirty volunteers with a mean age of 36.15 ± 9.55 years (range 21–56 years) and dry skin were recruited in two groups, one group to apply 5% urea containing hydrophilic petrolatum and the other 10% urea containing hydrophilic petrolatum. I n each cohort, the upper parts of right and left forearms were randomly assigned for twice a day application of commercial or compounded products. Whereas the right lower forearm was assigned for application of a cream-based formulation, the left lower one served as the control site and with application of no topical product. Biophysical assessments [transepidermal water loss (TEWL), skin hydration, friction coeffi cient, pH, and surface lipids], were performed before intervention, at 1 and 4 h after single application, and at 24 h and 1 week twice daily application. I n both groups, commercial and compounded moisturizers showed an appropriate and comparable effect on skin barrier function compared with cream- based formulation and no treatment area. However, commercial products led to better improvement in TEWL, 4 h after single application in both groups (p-value = 0.04). In case of 10% urea base formulation, the rate of increase in skin hydration was also signifi cantly higher for a commercial emollient than a compound ing product (57.48 ± 11.23 vs. 50.59 ± 11.42, p-value = 0.02). Comme rcial formulation led to higher acceptability and better improvement in the skin barrier function after single application, probably because of the infl uence of excipients. The present study did not fi nd suffi cient added value for cream-based pharmacy product relative to commercial one and suggests to be replaced in a similar condition. INTRO D UCTION AND BACKGROUND Pharm acy compounding is defi ned as customized developing of medical or cosmeceutical preparation for individuals with specifi c needs (1). Even though many commercial medi- cations and cosmeceuticals are available in the market, which makes medical practice Address all correspondence to Saman Ahmad Nasrollahi at snasrollahi@tums.ac.ir.

JOURNAL OF COSMETIC SCIENCE 202 more consistent, pharmaceutical compounding still has its role in dermatology. Apparently, market products were unable to resolve all needs of consumers on a personal level and cause some degrees of depersonalization in medical care (2,3). Derma tology and cosmetology are the most common areas of administration of com- pounding preparations. Corticosteroids, antibiotics, anti-acne agents, anesthetics, and moisturizers are commonly prescribed topical agents in compounding dermatology (4). Moist urizers are an important part of dry skin management, which are available in a variety of forms and formulations (5,6). Despite the discovery of novel ingredients for skin care urea is still one of the most useful molecules widely used in compounding and commer- cial moisturizers. It is a component of the natural moisturizing factor and plays an impor- tant role in the maintenance of skin hydration (7). When it comes to dry skin, many dermatologists tend to use compounded formulations, which let them personalize the concentrations (dosing) and vehicles, according to clinical picture and needs of the patient. Personalizing medications also makes products easier for patients to use, and enhances the treatment compliance (8). However, according to con- sideration of the Council of Europe, products prepared in pharmacies must offer added value relative to commercialized products (9). Pharmacy preparations are of added value if, due to medical, pharmaceutical, or personal reasons, they are needed by a specifi c pa- tient or by specifi c population groups with particular needs (9). In th e current study, we evaluated the effect of two different concentrations (5% and 10%) of urea-based compounded moisturizers on skin barrier function and hydration, compared with similar commercial products we also used. MATER IAL AND METHOD STUDY DESIGN AND PARTICIPANTS It wa s an intra-subject, double-blinded, randomized, controlled study. Two cohorts of healthy volunteers (men or women), with an age range of 18–60 years, with self-reported and clinically diagnosed dry skin, were recruited after signing written informed consent. Participants with a positive history of major skin diseases, or those using any topical preparations which might infl uence the skin hydration within past 7 d or used systemic corticosteroids or cytostatic drugs within past 2 weeks, were excluded from the study. Other exclusion criteria were active smoking, presence of any skin diseases on the fore- arms, and pregnancy or breastfeeding. The st udy was performed in compliance with the Declaration of Helsinki, and the study protocol was approved by the Ethics Committee of Tehran University of Medical Sciences (acceptance code: IR.TUMS.VCR.REC.1398.710). It was also registered in Iranian Register of Clinical Trials with registration code of IRCT20190210042676N9. TEST P REPARATIONS We use d two commercial water-in-oil products available in the local market (Golafshan Arayesh Cosmetic Laboratory, Tehran, Iran) as follows: