Hand washing is an important instrument to prevent disease transmission. Alcohol-based hand sanitizers are preferred for their germicide effectiveness. However, their high alcohol content is reported to cause skin dryness and sensitization upon repetitive use. Stratum corneum is the skin segment responsible for the skin ‘barrier’ against water loss, and is non-invasively assessed with Transepidermal Water Loss (TEWL). Dynamic tests such as plastic occlusion stress test (POST) are commonly used to increase this variable’s discriminative capacity. This study intended to evaluate the impact of the regular use of a commercially available alcohol-based gel on the epidermal ‘barrier’ function, using a bi-compartmental kinetic model that simulates the physiological distribution of water, where the data is analyzed as TEWL decay curves. 13 healthy females (21.6 ± 2.6 years old) were enrolled after informed written consent. Subjects washed the dorsum of one randomly chosen hand for 15 days with an 80% (v/v) alcohol gel. The contralateral hand served as control. TEWL obtained by evaporimetry (Tewameter TM300, Courage & Khazaka, Cologne, Germany) was measured on the middle region of the hand dorsum, on the projection of the second and third fingers, on days 1, 8 and 15. An occlusive patch was applied between the first and second fingers, for 24 hours on days 1 and 15. Upon removal, TEWL was continuously measured for 30 minutes, at a frequency of 0.1 Hz. The obtained TEWL curves were fitted by the kinetic model, and relevant parameters such as the evaporation half-time (t1/2 evap), the time required by the body to reduce its water loss by half, and the dynamic water mass (DWM), which represents the relevant weight of water involved in the process of desorption, were calculated. All statistical comparisons were done with the Wilcoxon signed-rank test (p<0.05). The occlusion causes a significant retention of water. After patch removal, TEWL initially increased and then progressively decayed towards its normal basal level. TEWL values increased significantly (p=0.028) on day 15 on the treated hand relative to the control hand. t1/2 evap and DWM also increased on day 15. t1/2 evap increased significantly (p=0.013) on the treated hand alone, while DWM increased in both hands, although non-significantly. Results have shown that, in the present experimental conditions, the regular use of the alcohol-based gel affected the epidermal barrier. This study also confirms the usefulness of this kinetic model in detecting subtle changes on TEWL dynamics.