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Topical Versus Oral Metronidazole Following Excisional Haemorrhoidectomy

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT03343509
Recruitment Status : Recruiting
First Posted : November 17, 2017
Last Update Posted : April 17, 2019
Information provided by (Responsible Party):
Andrew G Hill, MBChB, MD (Thesis), EdD, FACS, FRACS, University of Auckland, New Zealand

Brief Summary:

This study aims to determine if topical metronidazole reduces pain more than oral metronidazole following excisional haemorrhoidectomy. The trial will be a multi-centered, patient and investigator blinded superiority trial with two parallel groups and a primary outcome of pain scores during 14 days after surgery.

Group A will receive oral metronidazole and placebo cream. Group B will receive placebo tablets and topical metronidazole cream.

Condition or disease Intervention/treatment Phase
Hemorrhoids Postoperative Pain Drug: Metronidazole Oral Drug: Metronidazole Ointment Drug: Placebo Oral Tablet Drug: Placebo Ointment Phase 4

Detailed Description:

The pathogenesis of post-operative excisional haemorrhoidectomy pain is multi-factorial with secondary bacterial colonisation, inflammation and anal sphincter spasm/hypertonicity all purposed to play a role. Several pharmacological agents have been introduced in the last two decades targeting specific parts of the hypothesized pathway of pain pathogenesis showing promising improvements.

Metronidazole is part of the nitroimidazole class of antibiotics and primarily affects anaerobic bacteria and protozoa and traditionally has been used in surgical prophylaxis and treating anaerobic infections. It has been postulated to decrease pain following EH via two mechanisms; first by decreasing secondary bacterial colonisation and hence reducing post-operative inflammation; and second via a hitherto poorly understood direct anti-inflammatory response. The oral route has been initially investigated but topical administration has more recently been mooted for analgesia and theoretically reduces the unpleasant systemic side effects of oral administration. Our research group has recently completed a systematic review of both oral and topical administration of metronidazole. This review showed benefit in reducing postoperative haemorrhoidectomy pain from both routes of administration but this far there has been no comparison of the two routes.

Metronidazole has been proposed to have both anti-bacterial and pleiotropic anti-inflammatory properties but its precise mechanism of action is unknown. The increased understanding of this novel use of an agent with a known pharmacological profile will generally broaden our use of a simple, cheap and widespread agent. The investigators hope research into this drug will enable its use beyond that of haemorrhoidectomies, with possible pleiotropic applications into other similar operations.

Given the high prevalence of haemorrhoids in a vital segment of New Zealand's population, this research will contribute to improved outcomes for affected patients. Decreasing the significant post-operative pain will improve the quality of life for New Zealanders as well as affected populations worldwide. Socially and financially, it will enable earlier return to normal activity and reduce the burden on visits and readmissions to primary and secondary care, respectively.

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 120 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: A Prospective, Multicentre, Double-Blinded Randomised Controlled Trial Comparing Topical Versus Oral Metronidazole in Reducing Post-Operative Pain Following Excisional Haemorrhoidectomy
Actual Study Start Date : March 11, 2019
Estimated Primary Completion Date : June 2020
Estimated Study Completion Date : December 2020

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Hemorrhoids

Arm Intervention/treatment
Experimental: Group A - Oral
Oral metronidazole 400mg 3 times a day for 7 days Placebo ointment applied 3 time times a day for 7 days to affected region
Drug: Metronidazole Oral
Oral Metronidazole

Drug: Placebo Ointment
Placebo Ointment

Experimental: Group B - Topical
Topical metronidazole ointment 10% 3 times a day for 7 days Oral placebo tablets 3 times a day for 7 days
Drug: Metronidazole Ointment
Metronidazole Ointment

Drug: Placebo Oral Tablet
Placebo Tablet

Primary Outcome Measures :
  1. Daily Post-Operative Pain [ Time Frame: Day 7 ]
    Daily Post-Operative Pain Measured on Visual Analogue Scale (0 to 10)

Secondary Outcome Measures :
  1. Total Analgesia Use [ Time Frame: Day 7 ]
    Measured in Morphine Equivalent Doses

  2. Complication Rates [ Time Frame: Day 30 ]
    Short term complication rates including adverse reactions, bleeding, paraesthesiae, urinary retention, readmission

  3. Return to Normal Activity [ Time Frame: Day 30 (Followed up until returned back to normal) ]
    Time to return back to normal activity

  4. Return of Bowel Function [ Time Frame: Day 7 ]
    Time for first bowel motion

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   16 Years and older   (Child, Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • All patients undergoing excisional haemorrhoidectomy

Exclusion Criteria:

  • < 16 years of age
  • Have a simultaneous operation other than excisional haemorrhoidectomy
  • History of chronic pain
  • Previous allergy/adverse reaction to metronidazole
  • Patients unable to consent or complete data questionnaires due to cognitive impairment

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT03343509

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Contact: Weisi Xia, MBChB +64211207588

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New Zealand
Manukau SuperClinic, Counties Manukau District Health Board Recruiting
Auckland, New Zealand
Contact: Weisi Xia, MBChB   
Ormiston Hospital Recruiting
Auckland, New Zealand
Contact: Weisi Xia, MBChB   
Sponsors and Collaborators
University of Auckland, New Zealand
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Principal Investigator: Andrew G Hill, MBChB The University of Auckland
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Responsible Party: Andrew G Hill, MBChB, MD (Thesis), EdD, FACS, FRACS, Professor, University of Auckland, New Zealand Identifier: NCT03343509    
Other Study ID Numbers: MetHaemorrhoid
First Posted: November 17, 2017    Key Record Dates
Last Update Posted: April 17, 2019
Last Verified: April 2019
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No
Plan Description: Not to be shared

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Product Manufactured in and Exported from the U.S.: No
Keywords provided by Andrew G Hill, MBChB, MD (Thesis), EdD, FACS, FRACS, University of Auckland, New Zealand:
Postoperative analgesia
Additional relevant MeSH terms:
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Rectal Diseases
Intestinal Diseases
Gastrointestinal Diseases
Digestive System Diseases
Vascular Diseases
Cardiovascular Diseases
Anti-Infective Agents
Anti-Bacterial Agents
Antiprotozoal Agents
Antiparasitic Agents