Efficacy of metronidazole versus placebo in pain control after hemorrhoidectomy. Results of a controlled clinical trial

Abstract

Introduction: Hemorrhoidal disease occurs in 50% of people aged > 40 years and is the most common reason for anorectal surgery. Pain is the main complication. Multiple topical and systemic drugs have been investigated for pain control, but there is no ideal treatment. Metronidazole has been shown to decrease postoperative pain but is not used widely.Objective: To evaluate the effect of oral metronidazole versus placebo and to assess postoperative pain following hemorrhoidectomy.Material and methods: Controlled clinical trial in adult patients who underwent elective hemorrhoidectomy for grade III/IV hemorrhoids. Patients were assigned to receive metronidazole (500 mg q8 h orally; study group, SG) or placebo (control group, CG) for 7 days after surgery. Pain was assessed using a visual analog scale after surgery. Analgesic administration (time and use of analgesics) and resumption of daily life activities were also assessed.Results: Forty-four patients were included, 22 in each group. Postoperative pain differed significantly between the SG and CG at 6 h

Systematic review and meta‐analysis of the role of metronidazole in post‐haemorrhoidectomy pain relief

“…demonstrated a reduction in pain on days 1 and 4 but found no difference on days 5–7 and thus concluded that metronidazole did not reduce postoperative pain. These differences are surprising given the significant overlap in the studies considered by these two reviews and we would suggest that the differences are probably the result of several methodological differences between the two analyses.…”

“…Of the nine papers progressing to full text review one was excluded for not providing data on metronidazole alone as an intervention. A total of eight RCTs [17][18][19][20][21][22][23][24] were therefore included in this review with an aggregated population of 437 patients. Three of the studies used closed approaches [18,19,24] with the remaining five [17,[20][21][22][23] using open haemorrhoidectomy approaches.…”

“…A total of eight RCTs [17][18][19][20][21][22][23][24] were therefore included in this review with an aggregated population of 437 patients. Three of the studies used closed approaches [18,19,24] with the remaining five [17,[20][21][22][23] using open haemorrhoidectomy approaches. Seven studies [18][19][20][21][22][23][24] reported the severity of haemorrhoidal disease with five studies including only Grade III-IV [19][20][21][22]24], one using Grade II-III [18] and one Grade II-IV [23].…”

“…Type of sedation varied between studies. Six of the studies used general anaesthesia [17][18][19][20][21][22], one used spinal anaesthesia [23] and one study failed to specify the techniques used [24] (Table 2).…”

“…Consequently the study populations of these two analyses differ significantly in places such as the analysis of pain on day 7 where there are only two studies in common between our analysis and that of Wanis et al . . Further differences may also have arisen due to the retrospective calculation technique directly.…”