Opiate-Induced Tolerance & Hyperalgesia in Pain Patients
Status:
Completed
Trial end date:
2009-08-01
Target enrollment:
Participant gender:
Summary
Opiates such as morphine are the cornerstone medications for the treatment of moderate to
severe pain. Recent evidence suggests that pain patients on chronic opioid therapy become
more sensitive to pain (hyperalgesia) over time. There is also a long-standing notion that
analgesic tolerance to opioids (habituation) develops during chronic use even though this
phenomenon has never been prospectively studied. Our specific aims propose to prospectively
test the hypotheses that; 1) Pain patients on chronic opioid therapy develop dose-dependent
tolerance and/or hyperalgesia to these medications over time, 2) Opioid-induced tolerance and
hyperalgesia develop differently with respect to various types of pain, 3) Opioid-induced
hyperalgesia occurs independently of withdrawal phenomena, and 4) Opioid-induced tolerance
and hyperalgesia develop differently based on gender and/or ethnicity. This proposed study
will be the first quantitative and prospective study of tolerance and hyperalgesia in pain
patients and will have important implications for the rational use of opioids in the
treatment of chronic pain.
Phase:
Phase 4
Details
Lead Sponsor:
National Institute of General Medical Sciences (NIGMS)