Xingqi Daozhi Decoction for Antipsychotic-Induced Constipation

Overview

Antipsychotic medications are widely used to treat schizophrenia but may cause constipation, which can lead to abdominal discomfort, reduced quality of life, and poor treatment adherence. Xingqi Daozhi Decoction is a traditional Chinese medicine formula used to relieve constipation associated with qi stagnation. This study aims to evaluate the effectiveness and safety of Xingqi Daozhi Decoction for antipsychotic-induced constipation with a qi stagnation pattern. This is a single-center, randomized, double-blind, placebo-controlled exploratory study. A total of 46 participants with schizophrenia who developed constipation after taking antipsychotic medications will be enrolled. Participants will be randomly assigned to receive either Xingqi Daozhi Decoction granules or matching placebo granules twice daily for 8 weeks. Neither the participants nor the treating clinicians and outcome assessors will know the treatment assignment during the study. Participants will be evaluated regularly during treatment. The study will assess changes in bowel movements, constipation symptoms, constipation-related quality of life, and treatment safety. Participants will also undergo routine clinical and laboratory safety assessments, and adverse events will be recorded throughout the study. The primary outcome focuses on the proportion of participants who achieve an improvement in complete spontaneous bowel movements during treatment.

Antipsychotic-induced constipation is a common and clinically important adverse effect in patients receiving antipsychotic treatment. Anticholinergic and other pharmacological effects of antipsychotic medications may reduce gastrointestinal motility and intestinal secretion, leading to difficulty with defecation, abdominal distension, and other gastrointestinal symptoms. In severe cases, constipation may progress to serious gastrointestinal complications and may also negatively affect quality of life and adherence to psychiatric treatment. From the perspective of traditional Chinese medicine, constipation with a qi stagnation pattern is characterized by difficult defecation accompanied by symptoms such as abdominal distension, belching, frequent passage of gas, and a sensation of incomplete evacuation. Treatment is directed toward regulating qi, relieving stagnation, and promoting bowel movements. Previous clinical observations of Xingqi Daozhi Decoction in constipation with a qi stagnation pattern suggested potential therapeutic benefit and acceptable tolerability, providing the rationale for further evaluation in patients with antipsychotic-induced constipation. This exploratory study is designed to evaluate whether Xingqi Daozhi Decoction can improve constipation associated with antipsychotic treatment while maintaining acceptable safety and tolerability. Participants will undergo standardized clinical assessments throughout the treatment period, including evaluation of bowel habits, constipation-related symptoms, quality of life, psychiatric symptoms, treatment-emergent adverse effects, and routine safety parameters. Rescue treatment with glycerin enema may be used under predefined conditions when participants have no bowel movement for more than 3 consecutive days accompanied by abdominal discomfort, and its use will be recorded in the study documentation. In addition to clinical efficacy and safety assessments, stool samples will be collected at selected time points for exploratory analyses of gut microbial composition and metabolites, including 16S rRNA sequencing and short-chain fatty acid measurements. These exploratory analyses are intended to investigate possible biological changes associated with treatment and to provide preliminary evidence regarding potential mechanisms of action. After completion of the 8-week treatment period, participants may voluntarily enter an extended follow-up period of up to 1 year for continued clinical symptom assessment and telephone consultation.