Efficacy of Methylene Blue Plus Ropivacaine for Post-Hemorrhoidectomy Pain.

What Was Tested

In this phase 4 trial, researchers set out to test Methylene blue (non-peptide stack partner).

Revised Translation (Academic English): As one of the most prevalent anorectal disorders, mixed hemorrhoids continue to rely on the Milligan-Morgan hemorrhoidectomy as the gold-standard surgical approach.

Recent advancements in multimodal analgesia have highlighted the potential of local nerve blockers, with methylene blue (MB) gaining scientific interest due to its prolonged analgesic properties.

It had three arms (groups): High-Concentration Methylene Blue with Ropivacaine Group (experimental), Low-Concentration Methylene Blue with Ropivacaine (experimental) and Ropivacaine hydrochloride injection Group (no intervention).

Postoperative protocol: No routine preemptive analgesia administered.

The registry classes the interventions as drug.

Who Took Part

The registry lists 177 planned participants were the target.

It was open to people of any sex aged from 18 years up to 75 years.

Healthy volunteers were not accepted; participants needed the condition being studied.

Examples of who could join: Aged between 18 and 75 years. Diagnosed with Grade III-IV hemorrhoids according to the Goligher classification. Scheduled to undergo standard Milligan-Morgan hemorrhoidectomy. Procedure performed under spinal anesthesia alone.

The full record lists 4 inclusion and 7 exclusion criteria; among the exclusions: pregnancy or lactation; current immunotherapy or coagulopathies; contraindications to any protocol-specified agents (e.g., history of severe allergic reactions to methylene blue or ropivacaine).

How the Study Was Run

The set-up was randomized, parallel-group and open-label.

Random assignment meant chance, not the researchers, decided who got Methylene blue (non-peptide stack partner) and who got the comparison, which limits bias.

The Methylene blue (non-peptide stack partner) group and the comparison group ran side by side rather than switching.

Everyone knew when Methylene blue (non-peptide stack partner) was being given (open label), which is simpler to run but leaves more room for expectations to affect what is reported.

It started in 2025-08-30 with completion listed for 2026-08.

It ran at 1 site in China.

Its stated primary purpose is treatment.

What Was Measured

Researchers chose this as the main measure: Postoperative Numerical Rating Scale (NRS) Pain Scores (time frame: Within 30 days after surgery). Total Postoperative Analgesic Consumption (time frame: Within 30 days after surgery). Postoperative Quality of Life (QoL) Metrics (time frame: Within 30 days after surgery).

It also tracked 1 secondary outcome, for example Incidence of Postoperative Complications.

What This Means in Plain Language

Put simply, this is a phase 4, randomized trial of Methylene blue (non-peptide stack partner) in 177 people.

Its status is not yet recruiting; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the Methylene blue (non-peptide stack partner) compound page, all human trials.