 With technological advances, there were devices used to determine the flow of evaporation of skin - called by capacitance hygrometry analysis of transdermal water loss, known by its acronym in English TEWL. This is currently the most promising method for objective measurement of sweat, also used by cosmetics companies for new product research 31,32. The value is determined in grams per square meter per hour gm2h. Still no data in the literature to define the limits of TEWL and its application in real hyperhidrosis. But studies comparing the questionnaires mainly specific quality of life and objective measures of the amount of sweat and post-treatment 