Botulinum toxin injection for management of post-haemorrhoidectomy pain: an updated systematic review and meta-analysis of randomised clinical trials

TL;DR

This study reviews how botulinum toxin injections can help reduce pain after a specific type of hemorrhoid surgery, but the effects are short-lived.

Contribution

The study provides updated evidence on the effectiveness and safety of botulinum toxin for post-haemorrhoidectomy pain management.

Findings

Botulinum toxin significantly reduces pain on the first few days after surgery.

The analgesic effects are not sustained beyond day 4.

Botulinum toxin is safe with no significant increase in complications like faecal incontinence.

Abstract

Excisional haemorrhoidectomy remains the gold-standard treatment for grade III–IV haemorrhoids owing to the high success rate. However, post-operative pain management is an ongoing challenge. Botulinum toxin injection is thought to improve pain by targeting the internal anal sphincter spasm which occurs following haemorrhoidectomy. This systematic review and meta-analysis examines the effects of concurrent botulinum toxin injection on post-haemorrhoidectomy pain.

A search of MEDLINE, EMBASE and Cochrane Databases for randomised controlled trials (RCTs) of botulinum toxin injection compared with placebo for management of post-haemorrhoidectomy pain was conducted following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Outcomes assessed included daily post-operative pain scores assessed using an analogue scale (0–10), pain at first defecation, analgesia use, complication rates and time to return to work.

A total of seven RCTs assessing 340 patients who underwent an excisional haemorrhoidectomy were included. In total, seven studies (n = 340) found significant reduction in pain post-procedure with botulinum toxin use on day 1 (mean difference, MD −1.53; 95% confidence intervals, CI −2.12, −0.94; p < 0.00001), with similar findings on day 2 and 4 (MD −1.84, 95% CI −3.28, −0.41; p = 0.01 and MD −1.63, 95% CI −2.15, −1.09; p < 0.00001, respectively). However, the analgesic effects were not seen on subsequent analyses up to day 14. Botulinum toxin was seen to be safe, with no significant difference in faecal incontinence (MD 1.05, 95% CI 0.40, 2.75; p = 0.93) or urinary retention (MD 0.37, 95% CI 0.09, 1.53; p = 0.17).

Botulinum toxin use for pain relief post-excisional haemorrhoidectomy is safe and effective in the initial peri-operative period; however, the results were short-lived. Further, more robust randomised controlled trials are needed to strengthen these findings and determine the utility of botulinum toxin in this setting.

PROSPERO Register for Systematic Reviews Registration Number – CRD42024541351 on April 29 2024.

The online version contains supplementary material available at 10.1007/s10151-025-03137-z.

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