Comparison of the efficacy, safety, and tolerability of propiverine and oxybutynin for the treatment of overactive bladder syndrome

Aim: To compare the effects of propiverine and oxybutynin on ambulatory urodynamic monitoring (AUM) parameters, safety, and tolerability in patients with overactive bladder. Methods: This was a randomized, double-blind, placebo-controlled, multicentre, crossover study. Patients (n = 77) received two of the following treatments during two 2-week periods: propiverine 20 mg once daily, propiverine 15 mg three times daily, oxybutynin 5 mg three times daily, and placebo. AUM parameters, salivary flow, visual near point, and heart rate were assessed. Results: A consistent order in the efficacy between active treatment groups was observed for the reduction in mean involuntary detrusor contractions (IDCs; oxybutynin 15 mg <= propiverine 45 mg <= propiverine 20 mg). Differences between the oxybutynin and propiverine 20 mg groups were statistically significant for several AUM endpoints. Statistically significant differences between the oxybutynin and both propiverine groups were also noted in salivary flow rate and heart rate (oxybutynin 15 mg < both propiverine regimens) and in heart rate variability (both propiverine regimens < oxybutynin 15 mg). All active treatments lengthened visual near point. The incidence of dry mouth was significantly more pronounced in the oxybutynin group than in either propiverine group. Treatment with propiverine 45 mg resulted in the highest rates of constipation, lengthening of the visual near point, and effects on heart rate. Conclusions: Oxybutynin 15 mg was more effective than propiverine 20 mg in reducing symptomatic and asymptomatic IDCs in ambulatory patients. The primary differences between the two drugs were the incidence and type of adverse events, which varied with the antimuscarinic receptor specificity of each agent.