The use of oxybutynin in patients treated by means of botulinum neurotoxin A for neurogenic detrusor overactivity: an observational study

Abstract

This is an observational prospective noncontrolled study. We enrolled 105 patients affected by neurogenic detrusor overactivity (NDO) who underwent botulinum neurotoxin A (BONT-A) intradetrusor injection and were followed-up for 270 days. To investigate the use of oxybutynin after BONT-A administration in NDO patients. Careggi University Hospital in Florence and Tor Vergata University Hospital in Rome. Prospective data from two Italian centers were collected in 1 year. Patients showing limited efficacy but good tolerability and adherence to oxybutynin 5 mg three times a day (t.i.d.). were enrolled in the study. Patients received BONT-A intradetrusor injection (onabotulinumtoxinA, 300 U) with a trigone-sparing technique, and the use of oxybutynin was registered at every visit. 105 patients were included. At visit 1, only 30 patients (28.6%) used oxybutynin t.i.d., whereas 47 (45,2%) used a lower dosage and 28 (26.7%) stopped the therapy. At visit 2, 77.3% of patients who had reduced oxybutynin intake, maintained the dosage decided at visit 1. At visit 3, 51.9% returned to oxybutynin t.i.d.; 44.8% were on a reduced dosage and only 3 (2.9%) were not taking the drug. At visit 4, only 37.5% of patients were taking less than oxybutynin t.i.d. This study provides some important insights on the use of oral antimuscarinics in patients treated by means of BONT-A intradetrusor administration for NDO; in particular, it suggests that, after an initial reduction in the use of oxybutynin, patients tend to increase the dosage of this drug during the follow-up after the BONT-A treatment.