A Phase 4 interventional study of Fentanyl/Placebo injection in Pain, Postoperative, sponsored by University Hospital, Bordeaux. Completed at 1 site in France. Open to male participants aged 18 Years to 40 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-05-14.
Sponsored by University Hospital, Bordeaux · Phase 4, Interventional, and Health services research
Exaggerated pain and hyperalgesia are major issues after surgery and can lead to chronic pain. Opioid are parts of pain sensitization processes but remain absolutely necessary in the intraoperative period. NMDA receptor antagonists succeed in reducing this pain sensitization process. Recent studies show that in pain and opioid-experienced rats (POER) fentanyl ultra low doses do not induce analgesia, as observed in naive rats, but hyperalgesia. This is the first demonstration that a drug can induce opposite effect depending on individual history. We also observed a strong correlation between this hyperalgesic response in POER and the intensity of hyperalgesia they develop later, after inflammatory or surgical pain. The main aim of this study is to measure the dose effect response to fentanyl "ultra low doses" on human volunteer's nociceptive threshold, to determine if such an opposite response profile can be revealed.
Inclusion criteria :
In both groups:
In "operated" group:
- At least one history of peripheral surgery under general anesthesia with opioid in the past five years
Exclusion criteria :
In both groups:
In "healthy" group:
- Any history of general anesthesia or surgery
5,093 studies on the registry are indexed under Pain, Postoperative; 1,140 are open to participants now.
This study's enrollment of 48 is below the median of 75 across 4,344 interventional studies indexed under Pain, Postoperative.
Browse Pain, Postoperative studies →University Hospital, Bordeaux is the lead sponsor of 783 studies on the registry; 188 are open to participants now.
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In both groups:
In "operated" group:
Exclusion Criteria:
In both groups:
In "healthy" group:
0,5 µg/kg
Drug: Fentanyl/Placebo injection
0,05 µg/kg
Drug: Fentanyl/Placebo injection
0,005 µg/kg
Drug: Fentanyl/Placebo injection
NaCl 0,9 %
Drug: Fentanyl/Placebo injection
Ultra low dose intravenous injection
Nociceptive threshold evaluated with sternal electronical Von Frey mechanical stimulation. The stimulation will increase until the volunteer presses a trigger when the stimulation becomes painful.
Time frame: 5 min after injection, and every 15 min during 1 hour
Non invasive blood pressure (SBP, DBP), heart rate, respiratory rate, pulse oxymetry and cognitive functions evaluation (sedation score).
Time frame: all along the experimentation
This study is completed, as verified in Mar 2007. You cannot join it, but the record below documents what was studied.
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University Hospital, Bordeaux