Hemorrhoidectomy is an effective surgical treatment for advanced hemorrhoidal disease but is often associated with significant postoperative pain, which may delay recovery. One of the main contributors to pain after hemorrhoidectomy is spasm and increased tone of the internal anal sphincter.

This randomized, double-blind, placebo-controlled clinical trial evaluates whether preoperative injection of botulinum toxin type A into the internal anal sphincter, performed seven days before hemorrhoidectomy, can reduce postoperative pain compared with placebo. Adult patients with grade III-IV hemorrhoids scheduled for excisional hemorrhoidectomy will be randomized to receive either botulinum toxin A or saline injection prior to surgery.

Postoperative pain intensity, analgesic consumption, complications, functional outcomes, and patient satisfaction will be assessed during the first 30 days after surgery.

This multicenter, randomized, double-blind, placebo-controlled trial is designed to investigate the effect of preoperative botulinum toxin type A injection into the internal anal sphincter on postoperative pain following excisional hemorrhoidectomy.

Eligible adult patients with symptomatic grade III-IV hemorrhoids will be randomized in a 1:1 ratio to receive either botulinum toxin type A or placebo injection seven days prior to surgery. Botulinum toxin A will be injected into the internal anal sphincter in four quadrants using a standardized technique, while the control group will receive an identical volume of normal saline. Both patients and surgeons performing hemorrhoidectomy, as well as outcome assessors, will be blinded to treatment allocation.

All participants will subsequently undergo open or closed hemorrhoidectomy using standardized surgical and perioperative care protocols. Postoperative pain will be assessed using a visual analogue scale during the first seven postoperative days. Secondary outcomes include analgesic consumption, postoperative complications, length of hospital stay, transient fecal incontinence, time to first bowel movement, readmissions, and patient-reported satisfaction within 30 days after surgery.

The study aims to determine whether preoperative chemical sphincter relaxation with botulinum toxin A can improve postoperative recovery and reduce pain following hemorrhoidectomy.

Inclusion Criteria:

• Adults ≥18 years, male and female
• Symptomatic grade III-IV hemorrhoidal disease (Goligher), refractory to conservative treatment
• Scheduled for open (Milligan-Morgan) or closed (Ferguson) hemorrhoidectomy

Exclusion Criteria:

• Known hypersensitivity to botulinum toxin A, human albumin, or local anesthetics.
• Neuromuscular junction disorders (e.g., myasthenia gravis, Lambert-Eaton syndrome).
• Use of aminoglycosides or other agents interfering with neuromuscular transmission within 14 days.
• Coagulopathy or ongoing anticoagulant therapy not suitable for perioperative interruption.
• Active anorectal infection, fissure, abscess, or inflammatory bowel disease in the active phase.
• Previous anal sphincter surgery or baseline fecal incontinence.
• Pregnancy or breastfeeding.
• ASA ≥ III or significant systemic disease compromising anesthesia or wound healing.
• Participation in another interventional clinical trial within 30 days.

Individual participant data will not be shared due to institutional and ethical restrictions and because no data-sharing plan is specified in the study protocol.