Alpha-blockers before flexible ureteroscopy to ease ureteral access sheath placement.

Prospective, Randomized Study on the Efficiency of Alpha-Blockers Prior to Ureteral Sheath Placement in Flexible Ureterolithotripsy

Phase 4 Interventional Centro Universitário FMABC · NCT07124299

This trial will test whether taking an alpha-blocker for seven days before flexible ureteroscopy helps surgeons place the ureteral access sheath in adults with kidney stones.

Quick facts

PhasePhase 4
Study typeInterventional
Enrollment140 (estimated)
Ages18 Years and up
SexAll
SponsorCentro Universitário FMABC Academic / other
Locations1 site (Santo André, São Paulo)
Trial IDNCT07124299 on ClinicalTrials.gov

What this trial studies

This is a randomized prospective phase 4 trial enrolling adults with nephrolithiasis who are scheduled for flexible ureterorenolithotripsy at Centro Universitário FMABC. Participants are randomly assigned to receive an alpha-blocker for seven days before surgery or to proceed without preoperative alpha-blocker therapy. The primary outcome is successful ureteral access sheath placement without the need for a second procedure, and secondary outcomes include ureteral injury rates and the need for additional surgical interventions. The trial tests whether short-term pharmacologic relaxation of the ureter improves intraoperative efficiency and patient outcomes.

Who should consider this trial

Good fit: Adults aged 18 or older with kidney stones who are scheduled for flexible ureterorenolithotripsy, can provide informed consent, and are not already on chronic alpha-blocker therapy or recently stented/operated on the same side are the intended participants.

Not a fit: Patients with ureteral strictures, prior ureteral reconstructive surgery, recent ipsilateral ureteroscopy or double-J stent placement, chronic alpha-blocker use, or pregnancy are excluded and would not benefit from this protocol.

Why it matters

Potential benefit: If successful, preoperative alpha-blocker use could increase first-attempt sheath placement, reduce additional procedures and ureteral injuries, and shorten overall treatment for kidney stones.

How similar studies have performed: Some prior studies and clinical experience suggest alpha-blockers can relax the ureter and aid stone passage or instrument passage, but randomized data specifically for improving ureteral access sheath placement are limited.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Age ≥ 18 years
* Diagnosis of nephrolithiasis with surgical indication for flexible ureterorenolithotripsy
* Ability to provide written informed consent

Exclusion Criteria:

* Age \< 18 years
* Pregnancy
* History of ureteral stricture, prior ureteral reconstructive surgery, and/or abdominal or pelvic radiotherapy
* Prior ureteroscopy or ipsilateral double-J stent placement within the past 3 months
* Chronic use of alpha-blockers for benign prostatic hyperplasia or medical expulsive therapy for ureteral stones

Where this trial is running

Santo André, São Paulo

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions NephrolithiasisAlpha BlockerUreteral Access Sheath
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.