Evaluation of N-acetyl Cysteine for the Prevention of Post-endoscopic Retrograde Cholangiopancreatography Pancreatitis: A Prospective Double Blind Randomized Pilot Study

BACKGROUND: Acute pancreatitis is the most common serious complication of endoscopic retrograde cholangiopancreatography (ERCP) that can occasionally be fatal. Multiple drugs have been examined for the prevention of this side effect, with generally uncertain results. This study is an effort to prevent this complication by the use of oral N-acetyl cysteine (NAC). METHODS: A total of 100 patients who were candidates for ERCP were divided randomly into two groups. In the NAC (N) group, patients received 1200 mg NAC with 150 cc water orally 2 h before ERCP. In the placebo (P) group, 150 cc water was prescribed as a placebo. We measured serum amylase and lipase levels before and 24 h after ERCP. The prevalence of pancreatitis and duration of admission in each group were determined and compared. RESULTS: In group N there were 5 (10%) cases of pancreatitis, whereas in group P there were 14 (28%) cases, which was significant (risk reduction ratio: 2.8; p=0.02).The average admission time was 1.16±0.55 days in group N and 1.18±0.44 days in group P, which was not significant. CONCLUSION: There were significant differences in the prevalence of acute pancreatitis between the two groups. In addition, the number of need to treat (NNT) consisted of five cases for NAC. With regards to the above results and the safety profile of NAC, it could be used as a therapeutic agent for the prevention of post-ERCP pancreatitis. We recommend that the results of this study be verified by additional clinical trials.