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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
Opioid and adjuvant analgesics: compared and contrasted
Mohammed Ilyas Ahmed Khan1, Declan Walsh, Norman Brito-Dellan
1The Harry R. Horvitz Center for Palliative Medicine, Section of Palliative Medicine and Supportive Oncology, Cleveland Clinic Taussig CancerInstitute, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
The American Journal of Hospice & Palliative Care
|May 31, 2011
Summary
Adjuvant analgesics (AAs) enhance opioid pain relief and reduce side effects, offering unique actions for opioid-resistant pain. Unlike opioids, some AAs carry organ toxicity risks and have narrower therapeutic windows.
Area of Science:
- Pain Management
- Pharmacology
Background:
- Adjuvant analgesics (AAs) are non-opioid drugs that enhance pain relief.
- They can provide independent analgesic effects or additive properties when used with opioids.
- AAs are crucial for increasing the therapeutic index of opioids, managing opioid-resistant pain, and mitigating opioid-related side effects.
Purpose of the Study:
- To compare the characteristics and therapeutic roles of adjuvant analgesics (AAs) and opioids in pain management.
- To highlight the advantages and limitations of AAs in clinical practice, particularly in cancer pain.
- To inform optimal pain management strategies by understanding the distinct pharmacological profiles of AAs and opioids.
Main Methods:
- Comparative analysis of pharmacological properties, including analgesic effects, toxicity profiles, and therapeutic windows.
- Review of clinical applications and dosing considerations for both adjuvant analgesics and opioids.
- Examination of drug administration routes, metabolism, and potential for tolerance and withdrawal.
Main Results:
- Adjuvant analgesics offer unique analgesic actions and can reduce opioid doses and side effects, but some possess risks of permanent organ toxicity (e.g., NSAIDs and renal failure) and have narrower therapeutic windows than opioids.
- Opioids have a wide therapeutic window, flexible dosing, and predictable blood levels, but can cause withdrawal syndromes.
- AAs generally lack the route of administration versatility and rescue dosing suitability of opioids, with analgesic effects often observed within 1-2 days.
Conclusions:
- Adjuvant analgesics are essential tools in managing cancer pain, complementing opioid therapy.
- Understanding the distinct properties of AAs and opioids allows for optimized pain management strategies, balancing efficacy and safety.
- Appropriate use of AAs can significantly improve patient outcomes by reducing opioid burden and associated toxicities.
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