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Trial registered on ANZCTR

Registration number
Ethics application status
Submitted, not yet approved
Date submitted
Date registered
Date last updated
Date data sharing statement initially provided
Type of registration
Prospectively registered

Titles & IDs
Public title
The Role of Oral Metronidazole in the Management of Post Haemorrhoidectomy Pain
Scientific title
The Effect of Oral Metronidazole on Post Open Haemorrhoidectomy Pain
Secondary ID [1] 297693 0
Universal Trial Number (UTN)
Trial acronym
POHM trial
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Haemorrhoidal disease 311977 0
Condition category
Condition code
Surgery 310546 310546 0 0
Other surgery
Oral and Gastrointestinal 310709 310709 0 0
Other diseases of the mouth, teeth, oesophagus, digestive system including liver and colon

Study type
Description of intervention(s) / exposure
Intervention group: will take one 400mg metronidazole tablet, three times per day for 7 days after the patient has had their haemorrhoidectomy. This will commence in the evening (if the procedure was performed in the morning) or the following morning (if the procedure was performed in the afternoon).

Adherence to the intervention will be assessed by bottle returns.
Intervention code [1] 313923 0
Treatment: Drugs
Comparator / control treatment
o Control group: will take a placebo tablet (identical in appearance to the metronidazole tablets): one tablet, three times per day for 7 days.

The placebo will be PROSOLV® EASYtab SP. This consists of the following four ingredients: Microcrystalline Cellulose, Colloidal Silicon Dioxide, Sodium Starch Glycolate, Sodium Stearyl Fumarate.
Control group

Primary outcome [1] 319410 0
Post-operative pain days 1-7. This be assessed by using a Visual Analogue Score (VAS) ranging from 0-10 at each of these time points.
Timepoint [1] 319410 0
Days 1-7 post operation (this will be assessed daily during this time period).
Secondary outcome [1] 368043 0
Post-operative pain weeks 2-6. This be assessed by using a Visual Analogue Score (VAS) ranging from 0-10 at each of these time points.
Timepoint [1] 368043 0
This will be assessed weekly from weeks 2-6 post operation.
Secondary outcome [2] 368044 0
Return to work/normal daily activities. This will be assessed by asking the patient the date they returned to work. If the patient does not return to work, then the date they were able to complete their basic household chores.
Timepoint [2] 368044 0
6 weeks
Secondary outcome [3] 368045 0
Post-operative delayed wound healing. This will be assessed via clinical examination in the surgeon's rooms at 6 weeks post-operation. If the wound is still "open" (that is, the edges have not completely healed), then this will be considered delayed wound healing.
Timepoint [3] 368045 0
6 weeks
Secondary outcome [4] 368046 0
Post-operative complications: This outcome will be assessed at the time of 6 week post-operation follow-up in the surgeon's rooms. This information will be obtained from both the patient as well as the hospital medical records, to see if the following had occurred post-operation:
• bleeding (Defined as bleeding requiring re-admission to hospital and/or blood transfusion)
• urinary retention
• constipation
• re-admission to hospital
Timepoint [4] 368046 0
6 weeks

Key inclusion criteria
o Age greater than or equal to 18 years old
o Patient with grade III/IV internal haemorrhoids and/or external haemorrhoids, presenting for elective excisional open haemorrhoidectomy
o Patient capable of participating in informed consent for the study
o Patient willing to complete follow-up over the study period (6 weeks)
Minimum age
18 Years
Maximum age
No limit
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
o Patient unable or not willing to consent to procedure
o Patient allergy to metronidazole
o Patients who are immune suppressed
o If patient receives any antibiotics during the 6-week trial period
o Chronic kidney disease

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation will be performed by the pharmaceutical company producing the placebo and intervention tablets (PPI), which will be concealed from the study investigators. The placebo and intervention medications will be contained in numbered containers.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
Intervention assignment
Other design features
Phase 3 / Phase 4
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Not yet recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 302217 0
Name [1] 302217 0
Westmead Hospital, Colorectal Surgery Department
Address [1] 302217 0
Corner of Darcy Rd and Hawkesbury Rd
Westmead NSW, 2145
Country [1] 302217 0
Primary sponsor type
Dr Grahame Ctercteko
Westmead Hospital
Corner of Darcy Rd and Hawkesbury Rd
Westmead NSW, 2145
Secondary sponsor category [1] 302066 0
Name [1] 302066 0
Address [1] 302066 0
Country [1] 302066 0

Ethics approval
Ethics application status
Submitted, not yet approved
Ethics committee name [1] 302896 0
Western Sydney Local Health District Human Research Ethics Committee
Ethics committee address [1] 302896 0
Westmead Hospital
Corner of Darcy Rd and Hawkesbury Rd
Westmead NSW 2145
Ethics committee country [1] 302896 0
Date submitted for ethics approval [1] 302896 0
Approval date [1] 302896 0
Ethics approval number [1] 302896 0

Brief summary
We are planning on performing a double-blinded randomised controlled trial (RCT), investigating the role of oral metronidazole in the management of Post Open Haemorrhoidectomy pain.

Haemorrhoidal disease is a common benign condition, with conventional open haemorrhoidectomy remaining the gold standard for treatment. The main post-operative complaint is pain. Various methods have been used to optimise analgesia post-haemorrhoidectomy. The most widely used pharmacological agent is metronidazole, typically administered orally. However, the overall quality of previous studies investigating this have been few in number and generally of poor quality. It is common practice however, for the majority of surgeons both nationally and internationally to administer a prophylactic course of oral metronidazole to decrease post haemorrhoidectomy pain.

We hope to run our own RCT, double blinded, to assess whether oral metronidazole really does decrease post-operative pain. Patient will be either randomised to a seven day course of oral metronidazole (400mg TDS) or placebo. Patients will be followed up for 6 weeks, with the use of a 10-point Visual Analogue Scale (VAS) to assess their pain at various time intervals post-operatively.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 91770 0
Dr Grahame Ctercteko
Address 91770 0
Westmead Hospital
Corner Darcy Rd and Hawkesbury Rd
Westmead, NSW, 2145
Country 91770 0
Phone 91770 0
+61 288905555
Fax 91770 0
Email 91770 0
Contact person for public queries
Name 91771 0
Dr Grahame Ctercteko
Address 91771 0
Westmead Hospital
Corner Darcy Rd and Hawkesbury Rd
Westmead, NSW, 2145
Country 91771 0
Phone 91771 0
+61 288905555
Fax 91771 0
Email 91771 0
Contact person for scientific queries
Name 91772 0
Dr Grahame Ctercteko
Address 91772 0
Westmead Hospital
Corner Darcy Rd and Hawkesbury Rd
Westmead, NSW, 2145
Country 91772 0
Phone 91772 0
+61 288905555
Fax 91772 0
Email 91772 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No/undecided IPD sharing reason/comment
What supporting documents are/will be available?
No other documents available
Summary results
No Results