 Between July 2016 and December 2017, 670 consecutive patients older than 18 years who are scheduled to undergo diagnostic or therapeutic ERCP at the Anhui Provincial Hospital will be recruited for the study. Patients were randomized using opaque, sealed envelopes containing random numbers assigning them to undergo a spray of epinephrine epinephrine group or saline control group on the major papilla. A two proportion equality test will be conducted to explore whether incidence rates are different. Descriptive statistics including number N, mean, median, standard deviation, minimum and maximum, will be produced for all continuous variables. Frequency tables of number N and percentage of subjects will be produced for all categorical variables. 