IRCT20191231045969N2 IRCT 2020-09-30 Iran University of Medical Sciences The effect of rectal diclofenac on prevention of pancreatitis after ERCP ERCP (Endoscopic Retrograde Cholangio _pancreatography Effect of rectal diclofenac on prevention of pancreatitis after ERCP (Endoscopic Retrograde Cholangio_ Pancreatography) in comparison with control group 2019-09-23 anticipated 150 Complete https://irct.ir/trial/45502 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Not used, Assignment: Parallel, Purpose: Prevention, Randomization description: Patients will be randomly assigned to two groups of 75 controls and treatment group. Random allocation of patients will be done using random block method with permutations BA, BA, AB, AB, AA, BB, AB, BA, BA, AB, BB, AA. Thus, for group A, patients will receive diclofenac suppositories immediately before and after ERCP, and for group B, diclofenac suppositories will be given just before ERCP. Participant blinding and outcome assessment will be done single-blind. Since the intervention is performed in patients during anesthesia and patients are blinded in this regard, the study will be conducted blindly due to the lack of placebo. Participants and outcome assessors are not aware of grouping. The patient is explained that he or she may be randomly assigned to groups A and group B. Randomization unit: individual (individuals are assigned to treatment groups) Randomization tool: Random blocking, Blinding description: After obtaining the patient's consent, the patient is explained that he / she may accidentally receive diclofenac suppository before and after ERCP in group A and diclofenac suppository before ERCP in group B. Participant blinding and outcome assessment will be done single-blind. Since the intervention is performed on patients during anesthesia, patients will be blinded in this regard, and the study will be conducted blindly due to the lack of placebo. Participants and outcome assessors are not aware of grouping. The patient is explained that he or she may be randomly assigned to groups A and group B. The patient will only be informed of the suppository before performing the ERCP, and after performing the ERCP, the patient will not be informed of whether or not to prescribe the suppository. Only the operating room nurse who distributes the NSAID suppository is aware of the patient's presence in the intervention or control group that they are not involved in the research and will perform the random assignment operation. 3 Acute pancreatitis. Intervention 1: Intervention group: Patients receiving two diclofenac rectal suppositories 100 mg, one immediately before ERCP and the other immediately after ERCP.The name of the manufacturer of the consumable material of 100 mg diclofenac rectal suppository is Tehran Pakhsh Company. Intervention 2: Control group: Patients receiving a 100 mg rectal diclofenac suppository just before ERCP. The name of the company that manufactures the 100 mg diclofenac rectal suppository is Tehran Pakhsh Company. Undecided - It is not yet known if there will be a plan to make this available Justification or reason for indecision in sharing IPD is No more information.