EFFICACY EVALUATION OF DIFFERENT CREAM FORMULATIONS ON HEALTHY SKIN PROPERTIES

In this study three cream formulations were compared in order to assess the influence of different kind of excipients on the skin barrier and stratum corneum hydration. The first cream was formulated based on lipophilic emollients: petrolatum, paraffin oil, cetylstearilic alcohol, cetyl palmitate and paraffin, the second cream was formulated based on emollients (cetylstearilic alcohol, cetyl palmitate) and humectants (urea and glycerin), both as oil-in-water emulsions, and the third cream contained emollients (paraffin oil, cetyl palmitate, cetylstearilic alcohol) and humectants (urea and glycerin) in a multiple emulsion system, water1-oil-water2 type (W1/ O/W2), of second order and three components. The formulations were tested on the forearm of 10 healthy volunteers. The measurements were performed at room temperature (22 0 ± 2 0 C) and 45% ± 2% relative humidity. Skin conditions in terms of water content of the stratum corneum and transepidermal water loss (TEWL) were analyzed before creams application and at several time-intervals after cream application, during 4 hours. The best hydration was obtained when the multiple emulsions were used and also the duration of hydration was the greatest. The TEWL values are not significantly influenced by the studied formulations. Rezumat In acest studiu s-au comparat trei formulari de creme pentru a evalua influenţa diferiţilor excipienţi asupra barierei pielii si asupra hidratarii stratului cornos. Prima crema s-a formulat pe baza de emolienţi lipofili: vaselina, ulei de parafina, alcool cetilstearilic, palmitat de cetil si parafina; in a doua formulare s-au asociat emolienţi - alcool cetilstearilic, palmitat de cetil – si umectanţi – uree si glicerol. Ambele formulari sunt emulsii de tip ulei in apa. A treia crema s-a formulat ca emulsie multipla, asociind emolienţi – ulei de parafina, alcool cetilstearilic, palmitat de cetil si umectanţi – uree si glicerol. Cele trei formulari au fost testate pe 10 voluntari sanatosi. S-a inregistat hidratarea stratului cornos si pierderea de apa transepidermica, masuratorile fiind efectuate la temperatura camerei (22 0 ± 2 0 C) si la o umiditate relativa de 45% ± 2%, inainte de aplicarea cremelor si la diferite perioade de timp dupa aplicare. Emulsia multipla a determinat cea mai buna hidratare a stratului cornos, la toţi timpii evaluaţi. Valorile pierderii de apa transcutanate nu au fost influenţate semnificativ de cele trei formulari studiate.