Comparing oral antibiotics with no bowel preparation for elective colon surgery

A Randomised Study Comparing No Mechanical Bowel Preparation With Oral Antibiotics Alone in Patients Undergoing Elective Colon Surgery (REaCT-NSQIP)

Phase 4 Interventional Ottawa Hospital Research Institute · NCT03663504

This study is testing whether taking oral antibiotics before elective colon surgery can help patients avoid infections and improve their recovery compared to not using any bowel prep.

Quick facts

PhasePhase 4
Study typeInterventional
Enrollment452 (estimated)
Ages18 Years and up
SexAll
SponsorOttawa Hospital Research Institute Academic / other
Locations6 sites (Halifax, Nova Scotia and 5 other locations)
Trial IDNCT03663504 on ClinicalTrials.gov

What this trial studies

This study aims to compare the effectiveness of oral antibiotics alone versus no mechanical bowel preparation in patients undergoing elective colorectal surgery. It addresses the lack of consensus in clinical practice regarding preoperative bowel preparation methods. The trial will evaluate postoperative surgical infectious complications, length of hospital stay, incidence of C. difficile infections, patient quality of life, and cost-effectiveness. Data will be collected from the National Surgical Quality Improvement Program and patient questionnaires before and 30 days after surgery.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 and older scheduled for elective colon resection surgery without the need for mechanical bowel preparation.

Not a fit: Patients undergoing emergency surgery or those with contraindications to the oral antibiotics will not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved surgical outcomes and reduced complications for patients undergoing elective colon surgery.

How similar studies have performed: Other studies have explored similar approaches, but this trial aims to provide definitive evidence in a field with currently conflicting guidelines.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Patients undergoing elective, non-emergency colon, resection surgery or abdominal perineal resection and no other requirements exists for a mechanical bowel preparation (as determined by the operating surgeon)
* 18 years of age or older
* Able to provide oral consent

Exclusion Criteria:

* Contraindication to the oral antibiotics, including allergies or adverse reactions to either metronidazole or neomycin
* Undergoing a rectal resection with a planned anastomosis (these patients will all receive MBP)
* Emergency surgery where no opportunity to administer preoperative oral antibiotics exists
* Requirement for a MBP (i.e. rectal resection with pelvic anastomosis, intraoperative colonoscopy, or at the discretion of the treating surgeon

Where this trial is running

Halifax, Nova Scotia and 5 other locations

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 Elective Colon SurgeryOral AntibioticsPreoperative Mechanical Bowel PreparationSurgical Site InfectionC. difficile
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.