Aims: Lower urinary tract dysfunction is often occurs in patients with Parkinson's disease (PD), that is primarily induced by neurogenic detrusor overactivity (NDO) and negatively effect the quality of the patient's life. The aim of this study is to evaluate the acute effects of posterior tibial nerve stimulation (PTNS) on the urodynamic findings in the PD patients with NDO. Methods: Thirty-two patients with PD (19 [59.3%] men and 13 [40.6%] women) with NDO were included in the study. Mean age of the patients was 64.2 +/- 8.7 years (range 44-78). Urodynamic studies before and during PTNS were performed. Electrical stimulation was applied unilaterally from the medial malleolus and posterior to the edge of the tibia by using charge-compensated 200 mu sec pulses with a pulse rate of 20 Hz. Mean first involuntary detrusor (1st IDCV) contractions and means maximum cystometric capacity (MCC) before and during PTNS was compared. Results: Mean 1st 1DCV on standard cystometry was 145.2 +/- 41.1 (55-265) ml, while it was 244.7 +/- 51.7 (145-390) ml during PTNS. MCC on standard cystometry was 204.8 +/- 40.5 (115-320) ml, while it was 301.2 +/- 51.5 (230-395) ml during stimulation. Mean 1st IDC and mean MCC were significantly improved during PTNS. Conclusions: These results have demonstrated the objective acute effect of PTNS on urodynamic parameters. PTNS is acutely effective to suppress detrusor overactivity in PD patients. Neurourol. Urodynam. 28:62-67, 2009. (C) 2008 Wiley-Liss, Inc.