Fentanyl Ultra Low Doses Effects on the Nociceptive Threshold (NCT00454259) | Clinical Trial Compass
CompletedPhase 4
Fentanyl Ultra Low Doses Effects on the Nociceptive Threshold
France48 participantsStarted 2007-03
Plain-language summary
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.
Who can participate
Age range
18 Years – 40 Years
Sex
MALE
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
In both groups:
* 18-40 years old male volunteer
* Weight: 60 to 85 kg
* ASA score: 1
* Informed consent obtained from the patient
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:
* The patients do not accept inclusion to the study
* Drug or alcohol abuse history
* Chronic use of analgesic drugs or history of chronic pain
* Analgesic or opioid consumption within the 12hs preceding the fentanyl or placebo injection
* Neurological and/or psychiatric disorder, inability to give informed consent
* Psychological trauma within the two year preceding the inclusion
* Any contraindication to fentanyl use
* Use of any medication interacting with fentanyl
* Exclusion period from the national healthy volunteer register
In "healthy" group:
* Any history of general anesthesia or surgery
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
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.
Timeframe: 5 min after injection, and every 15 min during 1 hour