An interventional study of Active Pretibial TENS and Sham Pretibial TENS in Overactive Bladder (OAB), Botulinum Toxin Injection and Procedural Pain Relief, sponsored by Başakşehir Çam & Sakura City Hospital. Not yet recruiting. Open to female participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-07-16.
Sponsored by Başakşehir Çam & Sakura City Hospital · Not applicable, Interventional, and Supportive care
Overactive bladder is a common condition that causes a frequent, urgent need to urinate and can significantly reduce quality of life. When other treatments do not work well enough, doctors can inject a medication called onabotulinumtoxinA (a form of botulinum toxin) into the bladder wall. This procedure is often done in the office and is effective, but it can cause pain and anxiety during the injection.
Transcutaneous electrical nerve stimulation (TENS) is a non-invasive, drug-free method that uses mild electrical pulses delivered through pads placed on the skin. It is thought to reduce the sensation of pain and is already used to help with discomfort during some office procedures.
The purpose of this study is to find out whether applying TENS to the front of the lower legs (the pretibial area) reduces pain and anxiety in patients undergoing an intravesical onabotulinumtoxinA injection. Participants will be randomly assigned to one of two groups. In one group, the TENS device will be turned on (active). In the other group, the pads will be placed in the same location but the device will not be turned on (placebo). Neither the patient nor the doctor performing the assessment will know which group the patient is in.
Pain will be measured during the procedure using a visual analog scale. Anxiety will be measured before the procedure using a standard questionnaire, and patient satisfaction will be measured afterward. The study aims to enroll 68 participants in total.
Background: Overactive bladder (OAB) is a chronic urological condition that substantially impairs quality of life, and intravesical onabotulinumtoxinA (BTX-A) injection is an effective treatment option. Although performing this procedure in an office setting reduces hospital and operating room costs, the pain and anxiety experienced during the procedure can negatively affect patient comfort. Transcutaneous electrical nerve stimulation (TENS) is a non-invasive, non-pharmacological, and safe analgesic method believed to reduce pain perception through the gate control mechanism. Prior work has reported clinically meaningful reductions in pain scores when active TENS is applied during intravesical BTX-A injection; however, the effect of TENS applied specifically to the pretibial region during this procedure has not been previously investigated.
Objectives: The primary objective is to evaluate the effect of pretibial TENS on pain during office-based intravesical BTX-A injection, assessed using a Visual Analog Scale (VAS). Secondary objectives are to examine the relationship between pre-procedure anxiety level (measured with the Spielberger State-Trait Anxiety Inventory, STAI) and the pain experience, and to measure patient satisfaction using a 0-10 Likert scale.
Design: This is a randomized, double-blind, placebo-controlled trial. Participants will be randomized 1:1 using a sealed-envelope method. Envelopes will be prepared by an independent researcher not involved in conducting the study. Patients will be blinded to whether the device is active or inactive during the procedure, and blinding of the outcome assessment will be maintained.
Groups:
In both groups, the intravesical BTX-A injection will be performed according to the standard routine clinical protocol without any modification.
Measurements will be collected in the following order as part of the patient's routine clinical visit:
Sample size: Based on a power analysis assuming an effect size (Cohen's d) of 0.7, a significance level (alpha) of 0.05, and power (1-beta) of 0.80, 34 participants per group were required, for a total sample size of 68 participants.
Statistical analysis: Continuous variables will be compared using the Student t-test or the Mann-Whitney U test, as appropriate. Categorical variables will be analyzed using the chi-square test. The relationship between STAI and VAS scores will be assessed using Spearman correlation. A p-value \< 0.05 will be considered statistically significant.
858 studies on the registry are indexed under Urinary Bladder, Overactive; 127 are open to participants now.
This study's planned enrollment of 68 is close to the median of 70 across 649 interventional studies indexed under Urinary Bladder, Overactive.
Browse Urinary Bladder, Overactive studies →Başakşehir Çam & Sakura City Hospital is the lead sponsor of 109 studies on the registry; 36 are open to participants now.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
TENS pads are applied bilaterally to the pretibial region and the device is operated in active mode during the intravesical onabotulinumtoxinA injection. The standard intravesical BTX-A injection is performed according to routine clinical protocol.
Device: Active Pretibial TENS
TENS pads are applied to the same pretibial anatomical region but the device is not activated (sham). The standard intravesical BTX-A injection is performed according to routine clinical protocol, identical to the active group.
Device: Sham Pretibial TENS
Transcutaneous electrical nerve stimulation delivered through pads placed bilaterally on the pretibial region, with the device turned on (active stimulation) during the intravesical onabotulinumtoxinA injection.
Transcutaneous electrical nerve stimulation pads placed bilaterally on the pretibial region in an identical manner, but with the device not activated (no electrical stimulation delivered), during the intravesical onabotulinumtoxinA injection.
Procedural Pain Score (Visual Analog Scale, VAS)
Pain experienced during the intravesical onabotulinumtoxinA injection, assessed by the physician using a Visual Analog Scale ranging from 0 to 10 cm (0 = no pain, 10 = unbearable pain). Higher scores indicate greater pain. Mean VAS scores will be compared between the active TENS group and the placebo (sham) TENS group.
Time frame: During the intravesical onabotulinumtoxinA injection procedure (single assessment at the time of the procedure)
Patient Satisfaction (0-10 Likert Scale)
Patient satisfaction with the procedure, assessed after the injection using a 0-10 Likert scale. Higher scores indicate greater satisfaction. Mean satisfaction scores will be compared between the active TENS group and the placebo (sham) TENS group.
Time frame: Immediately after the intravesical onabotulinumtoxinA injection procedure (single assessment)
Pre-procedure Anxiety Level (State-Trait Anxiety Inventory, STAI)
Anxiety level measured before the procedure using the Spielberger State-Trait Anxiety Inventory (STAI). The relationship between the pre-procedure STAI score and the intraprocedural VAS pain score will be assessed. Higher STAI scores indicate greater anxiety.
Time frame: Immediately before the intravesical onabotulinumtoxinA injection procedure (single assessment)
No study locations are listed for this record.
Plan to share: Yes — Individual participant data will not be shared publicly. De-identified data may be made available upon reasonable request to the corresponding author, subject to institutional and ethics committee approval.
Supporting information: Study protocol
Time frame: Data will be available beginning 6 months and ending 36 months after publication of the main results.
Access criteria: De-identified data will be available to qualified researchers who provide a methodologically sound proposal, approved by the principal investigator and the local ethics committee. Requests should be directed to the corresponding author. A data use agreement may be required.
Start is estimated for Jul 2026; primary completion for Feb 2027, 7 months later.
Of 133 non-industry interventional studies with no phase under Urinary Bladder, Overactive, half reached primary completion within 22 months of starting (the median), counting those still running; a quarter within 11 and three quarters within 40. This study's planned 7 months is below that.
Counting every sponsor, half of 174 studies reached it within 19 months; a quarter within 10 and three quarters within 40.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
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