Oxybutynin for detrusor instability with adjuvant salivary stimulant pastilles to improve compliance: results of a multicentre, randomized controlled trial

Objective To test the hypothesis that compliance with oxybutynin would be improved if the severity of dry mouth could be reduced, thus leading to improved urinary symptom response and improved outcome, in a randomized, controlled trial of oxybutynin with or without salivary stimulant pastilles in patients with detrusor instability, Patients and methods Sixty-seven women with detrusor instability were randomized to a variable dose regimen of oxybutynin with (37) or without (30) salivary stimulant pastilles for 8 weeks. Patients were asked to complete a baseline voiding diary. In weeks 1 and 2, patients were encouraged to adjust the dose of oxybutynin themselves to achieve optimum symptomatic control, A second diary was completed in the sixth week and patients were reviewed at 8 weeks. The outcome measures were the compliance rate, followup attendance rate, maximum dose of medication, changes in voiding and incontinence episodes, and changes in severity of urgency and of dry mouth symptoms between the first and sixth week, Results Of the 67 women, 32 (47%) completed the study; the proportion completing was the same in both groups, Four patients had slopped the medication and there was no difference in the distribution of maximum dosage achieved between the groups. Both groups reported a reduced severity of urgency symptoms and increased severity of dry mouth. There were no differences in reported symptom change between the groups during the study, Conclusions The combination of oxybutynin and salivary stimulant pastilles does not improve compliance or symptom relief compared with oxybutynin alone: it does not allow a greater dose of oxybutynin to be tolerated.