Pain Relieving Effect of Sublingual Glycerol Trinitrate in Renal Colic: a Randomized Placebo-Controlled Trial

Introduction: Renal colic is caused by colicky spasms of ureters. As has been shown in previous experiments, glycerol trinitrate (TNG) can inhibit these muscular spasms. Objective: This study was performed to assess the pain relieving effect of TNG among patients referred due to renal colic pain to the emergency department (ED). Methods: This study is a randomized, placebo-controlled study on 60 patients with renal colic who were referred to the ED, who were diagnosed clinically to have renal colic, and their pain was more than 5 based on a visual analogue scale (VAS). The patient's pain was recorded at the moment of clinical diagnosis, and each one received one capsule, either 0.4 mg TNG or placebo, plus a 100 mg indomethacin suppository. The pain score was re-assessed after 5 and 30 min. The values were recorded and compared using SPSS-16 software. Results: Sixty patients with a mean age of 35.75 +/- 11.99 years were enrolled (73.3% male). Patients in the two groups were matched for age (p = 0.290), sex (p = 0.559), and the presence of microscopic hematuria (p = 0.292). Pain relief from the start point until the end of the intervention was statistical different in all studied patients (p < 0.05); but the comparison between the two groups showed no significant difference in this regard (p = 0.440). Conclusion: It is likely that adding TNG to an indomethacin suppository had no significant effects on better pain management of patients referred with renal colic to the ED.