Post-ERCP pancreatitis (PEP) remains the most common complication following endoscopic retrograde cholangiopancreatography (ERCP). Rectal indomethacin is one of the recommended medications given to prevent pancreatitis in high-risk patients undergoing ERCP.

This study aims to evaluate the effectiveness of diclofenac in preventing PEP, to compare its different routes of administration, and to determine the severity of pancreatitis in patients who develop PEP.

Databases from PubMed, ScienceDirect and COCHRANE Library were searched for randomized controlled trials (RCTs) comparing diclofenac with placebo in the prevention of PEPup to August 2020. Risk ratio at 95% Confidence Intervals (CI) were calculated to evaluate the incidence of the interested outcomes.

Eleven RCTs with a total population of 2,012 were reviewed in this study. Diclofenac was associated with a significant reduction in overall risk of PEP compared with patients with placebo (RR = 0.59; 95%, 0.47 0.74; P < 0.000001), with a mild heterogeneity (P = 0.05; I2 = 41%). Subgroup analyses showed that rectal diclofenac was the superior choice to significantly reduce the overall incidence of PEP(RR = 0.34; 95%, 0.23-0.51; P < 0.000001).

Rectal diclofenac significantly reduces the risk of PEPand therefore, should be recommended as routine for clinical use in adult patients who will undergo ERCP.