Sublingual Buprenorphine Efficacy in Renal Colic Pain Relief: A Randomized Placebo-Controlled Clinical Trial

INTRODUCTION: This study was designed to compare the analgesic efficacy of sublingual (SL) buprenorphine and intravenous (IV) ketorolac for renal colic pain relief. METHODS: The present study was carried out as a double-blind, double-dummy randomized clinical trial in patients diagnosed with acute renal colic attending the emergency department. The study subjects were 63 patients with confirmed renal stones. The subjects were randomly divided into two groups. One group, which included 32 patients, received SL buprenorphine tablets (2 mg) with an IV placebo, and another group, including 31 patients, received ketorolac tromethamine (30 mg) with a SL placebo. After medication, the pain of subjects was measured by a standard visual pain analogous scale (VPAS) in minutes 0, 20, 40, and 60 of study. Also, probable adverse effects were recorded. RESULTS: In 28.1% of patients in the buprenorphine group, the mean pain score decreased from 9.2 to 5.9, 2.8, and 1.5 after 20, 40, and 60 min, respectively, as determined by VPAS. Also, in 38.7% of patients in the ketorolac group, the mean pain score decreased from 9.1 to 5.5, 3.0, and 1.6 after 20, 40, and 60 min, respectively, as determined by VPAS. The two groups did not significantly differ for pain reduction at 20, 40, and 60 min (P value = 0.16, 0.34, and 0.3, respectively). No adverse effects were seen in the ketorolac group, but vomiting (18.8%), nausea (18.8%), and dizziness (21.9%) were detected in the buprenorphine group. CONCLUSIONS: We found no difference between SL buprenorphine and intravenous ketorolac in renal colic pain relief but more adverse effects in the buprenorphine group. Trial Registration Iranian Registry of Clinical trials identifier, IRCT2015041421773N1.