Clinical Trial: Study on the Development of Opioid Induced Hyperalgesia (OIH) After Exposure to Alfentanil

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: A Pilot Study of Prolonged, Intermittent Exposure to Alfentanil on Opioid-Induced Hyperalgesia in Healthy Volunteers

Brief Summary: The purpose of this study is to follow a person's response to experimental pain after multiple consecutive exposures to alfentanil or diphenhydramine to see if the person can tolerate the pain more, less, or the same at the end of the study.

Detailed Summary: This project investigates the phenomenon of opioid-induced hyperalgesia (OIH). Opioid analgesics, in addition to their therapeutic anti-nociceptive effects, under some conditions produce pro-nociceptive effects. This phenomenon of pain or pain sensitivity being increased by prior opioid administration is called opioid-induced hyperalgesia. It is thought to be relevant both to pain management complications and to complications of opioid dependence and its treatment. This study investigates the time-course of opioid-induced hyperalgesia development in healthy normal volunteers (N=12 completers), using a series of acute alfentanil administrations (15 mg/kg mg IM per day) spaced at 3-4 day intervals, with testing for pain tolerance using the cold pressor test (CPT), and mechanical quantitative sensory testing (MQST) each administered repeatedly over time within each testing day. The goal is to determine the time course of OIH development following acute opioid administration, and to assess whether this changes over repeated acute opioid administrations.
Sponsor: Johns Hopkins University

Current Primary Outcome: Change in Pain Tolerance (Time to Hand Removal in Seconds) in the Cold Pressor Test (Mean) at the 30 Minute Time Point [ Time Frame: 8 sessions over 4-6 weeks ]

Original Primary Outcome: change in pain tolerance (time to hand removal) in the cold pressor test [ Time Frame: 8 sessions over 4-6 weeks ]

Current Secondary Outcome:

  • Change in Pain Threshold (Time to Pain Onset) of Cold Pressor Testing [ Time Frame: 8 sessions over 4-6 weeks ]
  • Analgesic Effects (Pain Threshold and Tolerance) on Mechanical Quantitative Sensory Testing [ Time Frame: 8 sessions over 4-6 weeks ]


Original Secondary Outcome: Same as current

Information By: Johns Hopkins University

Dates:
Date Received: October 7, 2009
Date Started: February 2009
Date Completion:
Last Updated: August 9, 2013
Last Verified: August 2013