Clinical Efficacy of Sofpironium Bromide in Reducing Odor Intensity in Axillary Osmidrosis Complicated by Primary Axillary Hyperhidrosis: A Cohort Study

Objective: The efficacy of sofpironium bromide in managing axillary hyperhidrosis is well documented. However, limited information is available regarding its application in patients with axillary osmidrosis complicated by primary axillary hyperhidrosis. This study aimed to retrospectively examine the clinical efficacy of sofpironium bromide for odor reduction in patients with axillary osmidrosis complicated by primary axillary hyperhidrosis. Methods: We retrospectively reviewed the medical records of patients with axillary osmidrosis and primary axillary hyperhidrosis, from May 2022 to May 2023 in Nippon Medical School Musashi Kosugi Hospital, and data from those who had Hyperhidrosis Disease Severity Scale (HDSS) scores of 2 to 4 and were topically treated with sofpironium bromide once a day for 4 weeks were collected. Odor severity was assessed using both a 4-point physician scale and an 11-point patient subjective scale. Paired t test was used to compare odor severity assessment and HDSS scores before and after applying sofpironium bromide. Linear multiple regression analysis was conducted to identify factors influencing patients’ subjective odor reduction. Results: Data from a total of 87 patients were analyzed. Sofpironium bromide application significantly reduced axillary odor, with physician’s subjective odor scores improving from 2.39 ± 0.74 to 1.78 ± 0.78 ( t = 7.26, P < 0.001) and patient’s subjective scores from 7.37 ± 1.84 to 4.91 ± 2.68 ( t = 8.46, P < 0.001). Multivariate analysis revealed that a decrease in HDSS score, which was improved by sofpironium bromide application, was significantly associated with patients’ subjective odor reduction ( β = 1.98, standard error = 0.29, 95% confidence interval = 1.40–2.57, P < 0.001). Conclusion: Sofpironium bromide effectively reduced odor in patients with axillary osmidrosis complicated by primary axillary hyperhidrosis, providing a potential new non-invasive and economically feasible therapeutic option for this condition.