Hyperalgesia in Methadone Patients: Can it be Treated?
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|ClinicalTrials.gov Identifier: NCT00333242|
Recruitment Status : Unknown
Verified August 2008 by National Institute on Drug Abuse (NIDA).
Recruitment status was: Active, not recruiting
First Posted : June 2, 2006
Last Update Posted : January 11, 2017
|Condition or disease||Intervention/treatment||Phase|
|Opioid-induced Hyperalgesia||Drug: dextromethorphan||Phase 1|
Addressing the undertreatment of clinical pain has become a national priority, with a central goal being to identify effective interventions for those subgroups of patients most at risk for suffering unrelieved pain (NIH Program Announcement PA-01-115). In fact, the undertreatment of pain was recently ruled a form of patient abuse with a California court awarding one million dollars in damages to the family of such a patient. Novel data accumulated by our investigative group has shown that patients maintained on the mu-opioid agonist, methadone, for the treatment of addiction, are significantly hyperalgesic to cold-pressor experimental pain as compared to normal controls. This diminished pain tolerance, in addition to the contextual prohibitions associated with providing known opioid addicts with opioid analgesics, makes them a population uniquely vulnerable to the undertreatment of pain. Unfortunately, little is known about how to best manage the pain suffered by the over 120,000 methadone-maintained (MM) patients in this country, in part because the hyperalgesia they suffer appears to be akin to neuropathic pain and opioid-induced.
In the proposed series of studies, the Principal Investigator (a first-time R01 applicant) will build upon her previous studies validating and characterizing hyperalgesia in MM samples to explore it's underlying mechanism from a pharmacological perspective. Utilizing slightly different double-blind, placebo-controlled designs, the proposed work will evaluate the ability of three classes of medication (N-methyl-D-aspartate (NMDA)-antagonists, adjuvant anticonvulsant analgesics, and novel opioid analgesics) to diminish or reverse the opioid-induced hyperalgesia complicating the pain states suffered by MM patients. Specifically, in a sample of MM patients, (1) dextromethorphan, which interferes with the development of opioid-induced hyperalgesia, (2) gabapentin, which has proven efficacy in treating neuropathic pain, and (3) oxycodone, which has novel opioid activity, will each be evaluated for its ability to ameliorate or diminish the opioid-induced hyperalgesia in these patients as reflected by changes on pain threshold and tolerance to both cold-pressor and electrical pain, at peak and trough methadone blood levels. The results of this work will not only provide pharmacologic insight into the mechanisms underlying poor pain tolerance in this at-risk population, but also direction for the medical management of pain complicated by opioid-induced hyperalgesia.
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||40 participants|
|Intervention Model:||Parallel Assignment|
|Masking:||Triple (Participant, Care Provider, Investigator)|
|Study Start Date :||September 2002|
|Actual Primary Completion Date :||August 2006|
- Drug: dextromethorphan
dextromethorphan PO titrated to 480 mg/day x 5 weeks
- Pain tolerance [ Time Frame: 6 week ]
- Pain threshold [ Time Frame: 6 week ]
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00333242
|United States, California|
|UCLA School of Nursing|
|Los Angeles, California, United States, 90095|
|Principal Investigator:||Margaret A Compton, RN, PhD||UCLA School of Nursing|