Research on the Efficacy and Mechanism of Shouhui Tongbian Capsules in Treating Postoperative Constipation of Benign Anal and Rectal Diseases Based on Gut Microbiota Analysis

The goal of this clinical trial is to evaluate whether Shouhui Tongbian Capsule can improve postoperative constipation in adults aged 18 to 75 years after surgery for benign anorectal diseases, including hemorrhoids and anal fistula. The clinical trial will also evaluate the safety of Shouhui Tongbian Capsule and explore associations between treatment effects and changes in gut microbiota, metabolic profiles, and inflammatory indicators. The main questions are: Does Shouhui Tongbian Capsule improve constipation symptoms after benign anorectal surgery? Does Shouhui Tongbian Capsule reduce postoperative and defecation-related pain? Does Shouhui Tongbian Capsule improve quality of life and anorectal function? What adverse events occur during treatment? Are clinical improvements associated with changes in gut microbiota, metabolic profiles, or inflammatory indicators? Researchers will compare Shouhui Tongbian Capsule with lactulose to evaluate differences in efficacy and safety for postoperative constipation. Participants will: Receive either Shouhui Tongbian Capsule three times daily or lactulose once daily for 14 days Complete assessments of constipation symptoms, pain, quality of life, and anorectal function Provide stool and blood samples before treatment and on Day 14 Attend assessments during treatment and approximately 1 month after surgery Report adverse events and other medical problems during participation

Inclusion Criteria: Surgical indication for a benign anorectal disease, including hemorrhoids or anal fistula Diagnosis of postoperative constipation after benign anorectal surgery Postoperative constipation symptoms such as difficulty defecating, reduced bowel movement frequency, hard or lumpy stools, incomplete evacuation, anorectal obstruction, or abdominal distension Ability to tolerate the planned anorectal surgical procedure without related contraindications Consciousness and ability to cooperate with treatment, follow-up, and questionnaire assessments Written informed consent provided by the participant or legally authorized representative Age 18 to 75 years, inclusive Exclusion Criteria: Severe systemic disease, including serious psychiatric or immune disorders Severe infection Malignant tumor Severe organic disease of a major organ, including the heart, liver, or kidneys Pregnancy Breastfeeding Postpartum period Coagulation dysfunction Other anorectal disease that may affect outcome assessment Known allergy to either study treatment or any treatment component Any other condition considered by the investigators to make participation unsuitable