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Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities
Published on: July 29, 2014
Opioids for chronic nonterminal pain.
1Division of Pain Medicine, Massachusetts General Hospital, Department of Anesthesia and Critical Care, Harvard Medical School, Boston, MA 02114, USA. jballantyne@partners.org
Southern Medical Journal
|January 2, 2007
Summary
Chronic opioid therapy shows analgesic efficacy for chronic pain but has risks like side effects and addiction. A structured approach is needed to select patients and monitor treatment goals for safer, effective pain management.
Area of Science:
- Pain Medicine
- Pharmacology
- Clinical Therapeutics
Background:
- Chronic opioid therapy is widely used for chronic pain, including neuropathic pain.
- Evidence from randomized trials and observational studies supports opioid analgesic efficacy.
- Concerns exist regarding loss of efficacy, side effects, toxicity, and addiction risk.
Purpose of the Study:
- To review the evidence for and against chronic opioid therapy.
- To explore mechanisms of tolerance and opioid-induced hyperalgesia.
- To discuss ethical dilemmas and suggest a structured approach to chronic opioid treatment.
Main Methods:
- Review of existing evidence from randomized trials and observational studies.
- Exploration of mechanisms related to opioid efficacy, tolerance, and hyperalgesia.
- Discussion of patient selection, monitoring, and treatment goals.
Main Results:
- Evidence supports analgesic efficacy but is mixed for functional improvement and quality of life.
- Side effects are a common reason for treatment abandonment.
- Toxicity, hormonal/immune effects, and addiction risk are significant concerns, especially with prolonged high-dose use.
Conclusions:
- Chronic opioid therapy is not universally successful and carries significant risks.
- A structured, goal-directed approach is necessary for patient selection and monitoring.
- Future research should focus on identifying patients likely to benefit and developing opioids with lower abuse potential.
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