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The Relationships Between the Noradrenergic, Opioid and Pain System

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified May 2013 by d_yarnitsky, Rambam Health Care Campus.
Recruitment status was:  Not yet recruiting
Information provided by (Responsible Party):
d_yarnitsky, Rambam Health Care Campus Identifier:
First received: May 2, 2013
Last updated: May 9, 2013
Last verified: May 2013
The role of alpha2 receptor agonist on pain perception and modulation will be examined. In addition whether this is mediated through the opioid system will be examined. Pain perception and modulation will be examined before and after administration of Clonidine or placebo together with Naloxone or saline.

Condition Intervention
Experimental Pain Perception
Drug: Clonidine
Drug: Naloxone
Drug: placebo
Other: saline

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Participant, Investigator)
Primary Purpose: Basic Science

Resource links provided by NLM:

Further study details as provided by d_yarnitsky, Rambam Health Care Campus:

Primary Outcome Measures:
  • The changes in pain responses after administration of alpha 2 agonist and mu receptor antagonist [ Time Frame: 2 years ]
    The change in pain perception (pain thresholds and pain ratings of suprathresholds stimuli) and in the excitatory and inhibitory pain modulation responses (assessed by the temporal summation and conditioned pain modulation paradigms) will be examined before and after administration of alpha 2 agonist with and without mu receptor antagonist

Estimated Enrollment: 80
Study Start Date: May 2013
Estimated Study Completion Date: January 2015
Estimated Primary Completion Date: January 2014 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Clonidine+ Saline
Clonidine 0.15 mg and saline 0.15 mg/kg
Drug: Clonidine
Clonidine 0.15 mg
Other: saline
Active Comparator: Clonidine + Naloxone
Clonidine 0.15 mg and Naloxone 0.15 mg/kg
Drug: Clonidine
Clonidine 0.15 mg
Drug: Naloxone
naloxone 0.15 mg/kg
Active Comparator: Placebo +Naloxone
Placebo 0.15 mg+ naloxone 0.15 mg/kg
Drug: Naloxone
naloxone 0.15 mg/kg
Drug: placebo
Placebo Comparator: Placebo +saline
Placebo 0.15 mg+ saline 0.15 mg/kg
Drug: placebo Other: saline


Ages Eligible for Study:   18 Years to 40 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Healthy volunteers
  • Age 18-40
  • No chronic disease

Exclusion Criteria:

  • Subjects who suffer from chronic pain / pain syndrome
  • use of anti-depressant or anti-psychotic drugs
  • suffering from cardiovascular disease
  • breast feeding
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01851486

Contact: David Yarnitsky, Prof.

Rambam Health Care Campus Not yet recruiting
Haifa, Israel
Contact: David Yarnitsky   
Sponsors and Collaborators
Rambam Health Care Campus
  More Information

Responsible Party: d_yarnitsky, Professor, Head on Neurology Department, Rambam Health Care Campus Identifier: NCT01851486     History of Changes
Other Study ID Numbers: 0393-12-RMB.CTIL
Study First Received: May 2, 2013
Last Updated: May 9, 2013

Additional relevant MeSH terms:
Sensory System Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs
Antihypertensive Agents
Autonomic Agents
Adrenergic alpha-2 Receptor Agonists
Adrenergic alpha-Agonists
Adrenergic Agonists
Adrenergic Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Narcotic Antagonists processed this record on May 25, 2017