Efficacy of phloroglucinol and diclofenac sodium on pain relief for renal colic due to ureteral stones: a single-center, prospective randomized trial

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• Picked for Nephrology (top studies of the week, 2 August 2026).

Abstract

Renal colic is considered one of the most severe types of pain and requires prompt and effective analgesia. This study aimed to evaluate the efficacy of phloroglucinol in treating acute renal colic, comparing it to diclofenac sodium alone and in combination with phloroglucinol. In this single-center, randomized controlled trial, participants with acute renal colic (visual analog scale [VAS] score >4) due to ureterolithiasis were enrolled. They were randomly assigned (1:1:1) to receive diclofenac sodium, phloroglucinol, or a combination of both. The primary outcome was the pain relief rate at 30 min after treatment-defined as the proportion of participants with a ≥ 50% reduction in VAS score from baseline. Of 363 screened participants, 258 were enrolled and completed the trial (86 per group). The primary outcome was significantly better in the diclofenac sodium group than in the phloroglucinol group (55.8% vs. 70.9%; OR, 0.52; 95% CI, 0.28-0.97; p = 0.040). However, no significant difference was observed between the diclofenac group and the combination group (74.4% vs. 70.9%; OR, 1.19; 95% CI, 0.61-2.33; p = 0.608). Adverse events were significantly less frequent in the phloroglucinol group than in the other two groups. In conclusion, diclofenac sodium provides superior rapid pain relief and remains the optimal first-line treatment for acute renal colic. Overall, while it should not be used as a general alternative, phloroglucinol may be considered in patients in whom the use of NSAIDs is contraindicated. Clinical Trial Registration: https://www.chictr.org.cn/showproj.html?proj=275717, ChiCTR2500104563.

Abstract as published, via PubMed.