Clinical Trial: The Effect of High-dose Remifentanil on Established Capsaicin-induced Hyperalgesia in Human Volunteers

Study Status: Completed
Recruit Status: Unknown status
Study Type: Interventional

Official Title: The Effect of High-dose Remifentanil on Established Capsaicin-induced Hyperalgesia in Human Volunteers

Brief Summary:

Treatment of chronic pain is a major clinical challenge since chronic pain is frequent and leads to deterioration of quality of life. An injury or wound can lead to long term changes in the nervous system that make the skin more sensitive at and near the injury; this is termed hyperalgesia and occurs through long term depotentiation (LTP), i.e., a change in the synaptic interaction between neurons.

Opioids are the gold standard for the symptomatic therapy of moderate to severe pain. Now, in animal studies the investigators have discovered previously unrecognized effects of opioids.

Intradermal injection of capsaicin (injection of pepper extract into the skin) is an established pain model in humans. The investigators want to test the influence of remifentanil, an ultra-short acting opioid, on hyperalgesia observed after intradermal capsaicin in human volunteers in a double blind cross-over prospective active placebo controlled clinical trial.


Detailed Summary:
Sponsor: Medical University of Vienna

Current Primary Outcome: Area of pin prick hyperalgesia [ Time Frame: 0-6 hours ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Pain immediately after injection [ Time Frame: 0-15 min ]
  • Stimulus-response (SR) function to a set of modified rigid von Frey filaments (8-512 mN) [ Time Frame: 0-6 hours ]
  • Heat pain threshold within the area of mechanical hyperalgesia [ Time Frame: 0-6 hours ]
  • Mechanical pain threshold within the area of pin prick hyperalgesia, area of dynamic allodynia to brush [ Time Frame: 0-6 hours ]
  • Adverse effects [ Time Frame: 30 and 59 min after infusion of study medication ]


Original Secondary Outcome: Same as current

Information By: Medical University of Vienna

Dates:
Date Received: April 21, 2009
Date Started: June 2009
Date Completion: March 2010
Last Updated: November 17, 2009
Last Verified: November 2009