Wolosker N, Kauffman P, de Campos JRM, et al. - Researchers conducted the study for analyzing the substantial experience obtained with the use of oxybutynin as an initial treatment of hyperhidrosis (HH), characterized by exaggerated sweating in a specific region due to hyperfunction of the sweat glands, in a large series of patients (n = 1,658) after 12 years of utilizing this medication in the service. From May 2006 to June 2018, patients treated with oxybutynin for HH were analyzed. Participants in the study were divided into four groups based on the main site of HH: the plantar group, the axillary group, the facial group, and the palmar group. In more than 94% of the cases, pretreatment quality of life was poor or very poor and the palmar group had the worst quality of life. An improvement was noted in the quality of life in 77% of patients after treatment. In all groups, 24.9% of all patients reported intense dry mouth. This research involved a large number of patients who were treated for a long period of time and showed the successful efficacy of oxybutynin treatment for hyperhidrosis at the main sweating sites.