Real-life experience with oral oxybutynin long-term continuous therapy in severe hyperhidrosis and systematic review of the literature

Hyperhidrosis is a disorder of excessive sweating severely impacting on patient's quality of life (Qol). Several studies have been published about oral oxybutynin, but no studies focused on the achievement of complete clinical and Qol response. The aim of this study was to report our real-life experience with oral oxybutynin in patients with severe hyperhidrosis significantly affecting their Qol. In this cohort retrospective study, we enrolled, in a 3-year period, patients affected by severe hyperhidrosis with poor Qol, continuously treated with oral oxybutynin. Our outcome was the obtainment of complete clinical and Qol improvement. A systematic review of the literature was also performed reporting efficacy and safety of oral oxybutynin for primary hyperhidrosis. We enrolled 62 patients, of which 53 (85.5%) received a mean daily dose of 10 mg and nine (15.5%) of 5 mg. Complete clinical response was achieved in 77.4% (48/62) of cases, while complete Qol improvement occurred in 51.6% (32/62) of cases. Adverse events were only reported as mild, with dry mouth being the most frequently observed (16.1%). Kaplan-Meier survival analysis highlighted that both median clinical and Qol complete responses were reached after 1 year of continuous therapy with oral oxybutynin. The main limitation of our study is the small number of patients enrolled. Long-term therapy with oral oxybutynin for severe hyperhidrosis, continuously administered at a mean daily dosage of 5 to 10 mg, allowed the majority of our patients to reach both clinical and Qol complete improvement, without significant adverse events.