A Role of Intravesical Capsaicin Instillation in Benign Prostatic Hyperplasia with Overactive Bladder Symptoms: The First Reported Study in the Literature
Phitsanu Mahawong MD*, Bansithi Chaiyaprasithi MD*, Suchai Soontrapa MD*, Pimolvan Tappayuthapijarn MS**
Affiliation : * Division of Urology, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok ** Department of Pharmacology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok
Objective : To study the treatment efficacy of capsaicin, in the cases of benign prostatic hyperplasia with
overactive bladder symptoms.
Materials and Methods : A prospective study of 20 benign prostatic hyperplasia patients whose overactive
bladder symptoms were not improved by alpha1 blockers. All of them underwent intravesical capsaicin
instillation at the Faculty of Medicine Siriraj Hospital, Bangkok, between 2004 and 2006. Both clinical and
urodynamic data were evaluated before and after treatment.
Results : Mean urgency decreased from 6.7 + 5.1 at baseline to 2.0 + 2.3 (p < 0.005), 1.4 + 2.4 (p < 0.005), and
1.3 + 2.2 (p < 0.005) at 1, 3, and 6 months. Mean urge incontinence decreased from 1.7 + 3.5 at baseline to 0.5
+ 1.3 (p = 0.148), 0.4 + 1.2 (p = 0.114), and 0.3 + 1.1 (p = 0.085) at 1, 3, and 6 months. Mean urinary
frequency decreased from 13.7 + 3.3 at baseline to 10.5 + 2.8 (p < 0.005), 9.6 + 2.0 (p < 0.005), and 9.5 + 2.6
(p < 0.005) at 1, 3, and 6 months. Mean nocturia decreased from 4.7 + 2.4 at baseline to 3.1 + 2.2 (p < 0.005),
2.7 + 1.2 (p < 0.005), and 2.9 + 1.6 (p < 0.005) at 1, 3, and 6 months. Mean first desire to void increased from
172.5 + 100.4 ml at baseline to 210.6 + 99.5 ml (p = 0.016) at 1 month. Mean maximal cystometric capacity
increased from 350.3 + 165.9 ml at baseline to 397.4 + 165.7 ml (p = 0.012) at 1 month. Peak flow rate,
detrusor pressure, and post void residual urine were not affected. No serious adverse effect occurred in this
study.
Conclusion : Intravesical capsaicin instillation is an effective treatment for overactive bladder symptoms in
benign prostatic hyperplasia patients.
Keywords : Capsaicin, Benign prostatic hyperplasia, Overactive bladder
