Aims Pancreatitis is the most common complication of endoscopic retrograde cholangiopancreatography (ERCP). Rectal nonsteroidal anti-inflammatory drugs (rNSAIDs) administration is considered as standard of care to reduce the risk of post-ERCP pancreatitis. It has been suggested that aggressive hydration may further reduce this risk. Guidelines already recommend aggressive hydration. However, multicentre randomised trials studying the added value of aggressive hydration in patients receiving prophylactic rNSAIDs are lacking. We, therefore, performed a trial to investigate the combination of aggressive hydration and rNSAIDs.