The Effect of Bethanechol Chloride with an α-adrenergic Blocker in Patients with Impaired Detrusor Contractility

Abstract

Purpose: Bethanechol enhances detrusor contraction and α1-blockers reduce bladder outlet resistance. We evaluated the effects of bethanechol with doxazosin in patients with impaired detrusor contractility. Materials and Methods: Fifty-six patients that had confirmed detrusor underactivity with at least 150ml of postvoid residual urine volume (PVR) based on a urodynamic study were enrolled. The initial dosage of bethanechol given was 75mg/day, and the dosage was gradually increased to 150mg/day if necessary. Doxazosin gastro-intestinal therapeutic system (GITS) (4mg) was also given. The effect of the treatment was evaluated by a urine flow test, the amount of PVR, and frequency of clean intermittent catheterization (CIC). Results: The mean follow-up period was 6 months (range, 1 to 9 months). After treatment, the mean PVR decreased from 251.8±149.6ml to 136.4± 153.2ml (p<0.001) and was less than 100ml in 22 (39%) of the 38 patients that showed a decrease. The maximum flow rate (Qmax) increased from 8.7±4.7ml/s to 11.1±5.6ml/s (p=0.024) and was more than 5ml/s in 13 patients (23%). Five of the 18 patients that previously required CIC could discontinue this treatment and another nine patients showed a decrease in the frequency. The mean daily frequency of CIC was reduced from 3.2 to 1.5 (p=0.004). Ten of the 12 patients that were not able to void became capable of voluntary voiding. Five patients (9%) complained of adverse reactions and four of them were taken off the medication. Conclusions: The combination therapy of bethanechol with doxazosin improved emptying ability in patients with impaired detrusor contractility. (Korean J Urol 2007;48:1040-1043) 󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏