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

Participants assigned to the Shouhui Tongbian Capsule group will receive routine postoperative care together with oral Shouhui Tongbian Capsule for 14 consecutive days. The dose will be two capsules per administration, three times daily, taken with warm water approximately 30 minutes after breakfast, lunch, and dinner. Each capsule contains 0.35 g of the approved marketed product. During the treatment period, other laxatives, probiotics, Chinese herbal medicines, or drugs that may affect intestinal motility or gut microbiota will generally be prohibited unless clinically necessary. Medication use, treatment adherence, drug dispensing, returns, adverse events, and any rescue treatment will be recorded throughout the study.

Participants assigned to the lactulose group will receive routine postoperative care together with lactulose oral solution for 14 consecutive days. Lactulose will be administered orally at a dose of 15 mL once daily in the morning. Participants will receive both verbal and written instructions on the dose, administration method, and treatment schedule. During the study, other laxatives, probiotics, Chinese herbal medicines, or medications that may affect intestinal motility or gut microbiota will generally be prohibited unless clinically necessary. Treatment adherence, concomitant medications, adverse events, and any rescue treatment for severe constipation, pain, or postoperative discomfort will be recorded in the case report form.