Delivering safe and effective analgesia for management of renal colic in the emergency department: a double-blind, multigroup, randomised controlled trial.

Background: The excruciating pain of patients with renal colic on presentation to the emergency department requires effective analgesia to be administered in the shortest possible time. Trials comparing intramuscular non-steroidal anti-inflammatory drugs with intravenous opioids or paracetamol have been inconclusive because of the challenges associated with concealment of randomisation, small sample size, differences in outcome measures, and inadequate masking of participants and assessors. We did this trial to develop definitive evidence regarding the choice of initial analgesia and route of administration in participants presenting with renal colic to the emergency department.