Retention enema with Chinese botanical drug decoctions as an adjunct to conventional treatment for gastrointestinal dysfunction in severe acute pancreatitis: a systematic review and meta-analysis of randomized controlled trials

Objective To evaluate the efficacy and safety of adding retention enemas with Chinese botanical drug decoctions to conventional treatment for gastrointestinal dysfunction in severe acute pancreatitis (SAP), and to appraise how the preparations were reported. Methods Seven English and Chinese databases were searched to 21 January 2026 for randomized controlled trials (RCTs). We assessed risk of bias (RoB 2), data integrity, preparation reporting (ConPhyMP) and certainty of evidence (GRADE), and performed random-effects meta-analyses with Hartung–Knapp confidence intervals. Results Twenty-five RCTs (1,963 participants), all from China, were included; one further report was a duplicate publication. Five trials that reproduced the data of earlier trials from other hospitals were excluded from the primary analysis (20 trials, 1,643 participants). No trial was blinded or registered, and none chemically characterised its preparation. The enema was associated with shorter times to first defecation (SMD −2.79, 95% CI −4.37 to −1.20; 7 trials), first flatus (SMD −2.00, −3.64 to −0.35; 6 trials) and recovery of bowel sounds (SMD −2.88, −5.70 to −0.06; 5 trials), and with a higher effectiveness rate (OR 4.29, 2.70 to 6.81; 14 trials), but heterogeneity was very high and prediction intervals included no effect for the recovery times, and small-study effects were evident for the effectiveness rate. Adverse events were reported in six trials (OR 0.64, 0.20–1.99). Certainty was very low for all outcomes except length of stay (low). No clear evidence of a difference between Chengqi-type and other formulas was found, but the subgroup analyses were underpowered and do not establish equivalence. Conclusion Very low-certainty evidence suggests that botanical drug retention enemas may hasten the recovery of gastrointestinal function in SAP. Because the trials were small, unblinded, at high risk of bias and partly affected by duplicated data, and the preparations were heterogeneous and uncharacterised, the findings cannot be attributed to any specific preparation, and safety remains uncertain. Rigorous, registered trials using characterised preparations are needed. Systematic Review Registration https://www.crd.york.ac.uk/PROSPERO/view/CRD420261301311 , Identifier, CRD420261301311.