Intramuscular etofenamate versus diclofenac in the relief of renal colic - A randomised, single-blind, comparative study

Objective: To compare the efficacy and adverse effects of intramuscular etofenamate and intramuscular diclofenac in the relief of acute renal colic. Patients and methods: A multicentre, randomised, single-blind study was performed in 119 patients admitted to the emergency room for renal colic. Patients were assigned to treatment with either etofenamate 1000mg or diclofenac 75mg, both administered intramuscularly. Pain was self-assessed using a 4-point verbal rating scale (VRS) and a visual analogue scale (VAS) just before drug administration and 30, 60, 120 and 240 min later. Results: The two groups were similar with regard to baseline characteristics. The percentages of patients who reported an improvement in the VRS at 60 min post-administration (primary variable) were 84.5% with etofenamate and 83.3% with diclofenac (p = 0.73). At the other timepoints (30, 120 and 240 min), the proportions of patients improved were, respectively, 69.5%, 82.6% and 79.3% in the etofenamate group, and 75.0%, 81.7% and 80.0% in the diclofenac group. The VAS score showed a statistically significant improvement in both groups, but no differences between groups were found. Analgesic rescue medication was required by 11 (18.6%) patients in the etofenamate group and by 12 (20.0%) patients in the diclofenac group. Mild to moderate adverse events were reported by 3.4% of patients receiving etofenamate and by 5.0% of patients receiving diclofenac. Conclusion: Etofenamate and diclofenac were similarly effective and tolerated in the relief of acute renal colic.