The DOI matches its Crossref record; 19 of the 19 references it cites were found in a registry or an index.
Synergistic affective analgesic interaction between delta-9-tetrahydrocannabinol and morphine
Abstract
Evidence for an analgesic interaction between delta-9-tetrahydrocannabinol (Delta(9)-THC) and morphine was sought using an experimental pain model applied to normal volunteers. The study incorporated a double blinded, four treatment, four period, four sequence, crossover design. Subjects received Delta(9)-THC 5 mg orally or placebo and 90 min later morphine 0.02 mg/kg intravenously or placebo. Fifteen minutes later subjects rated the pain associated with the application of thermal stimuli to skin using two visual analog scales, one for the sensory and one for the affective aspects of pain. Among sensory responses, neither morphine nor Delta(9)-THC had a significant effect at the doses used, and there was no significant interaction between the two. Among affective responses, although neither morphine nor Delta(9)-THC had a significant effect, there was a positive analgesic interaction between the two (p = 0.012), indicating that the combination had a synergistic affective analgesic effect. The surprisingly limited reported experimental experience in humans does not support a role for Delta(9)-THC as an analgesic or as an adjunct to cannabinoid analgesia, except for our finding of synergy limited to the affective component of pain. Comparison of our results with those of others suggests that extrapolation from experimental pain models to the clinic is not likely to be a straight-forward process. Future studies of Delta(9)-THC or other cannabinoids in combination with opiates should focus upon clinical rather than experimental pain.
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“In this study, the doses of morphine or THC used alone did not elicit a significant analgesic effect, but combination of the drugs showed an enhanced analgesic effect with respect to the affective component of pain.”
From The endogenous cannabinoid system: a budding source of targets for treating inflammatory and neuropathic pain (2018) · cites this paper as Roberts et al, 2006
In the citing paper
“Combination of delta-9-THC and morphine did not have an effect on pain intensity.The combination resulted in lower ratings of unpleasantness of pain compared with either drug alone”
From Opioid-Sparing Effect of Cannabinoids: A Systematic Review and Meta-Analysis (2017) · cites this paper as Roberts 2006
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Emerging strategies for exploiting cannabinoid receptor agonists as medicines
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Donvito, G., Nass, S. R., Wilkerson, J. L., Curry, Z. A., Schurman, L. D., Kinsey, S. G., & Lichtman, A. H. (2018) · Neuropsychopharmacology · doi:10.1038/npp.2017.204 · Cited by 301
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Metadata
- Authors
- Roberts, J. D., Gennings, C., & Shih, M.
- Affiliations
- Virginia Commonwealth University (US)
- Los Angeles County Department of Public Health (US)
- Corresponding author
- Roberts, John D.
- Venue
- European Journal of Pharmacology
- Publisher
- Elsevier BV
- Published
- 2006-01
- Volume
- 530
- Issue
- 1-2
- Pages
- 54-58
- ISSN
- 0014-2999 (ISSN-L)
- OpenAlex
- W2145508348
- Cited by
- 103
- References
- 19
- Citations by year
- 2026: 1 · 2025: 2 · 2024: 5 · 2023: 5 · 2022: 5 · 2021: 6 · 2020: 8 · 2019: 10 · 2018: 7 · 2017: 9 · 2016: 1 · 2015: 5 · 2014: 5 · 2013: 5 · 2012: 7
- FWCI
- 1.70
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- European Journal of Pharmacology (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Health Sciences › Medicine › Pharmacology (medical) › Cannabis and Cannabinoid Research
- Health Sciences › Medicine › Physiology (medical) › Pain Mechanisms and Treatments
- Health Sciences › Medicine › Anesthesiology and Pain Medicine › Pain Management and Opioid Use
- Keywords
- delta-9-tetrahydrocannabinol, morphine, analgesic interaction, synergistic analgesia, affective pain, sensory pain, experimental pain models, thermal pain
- MeSH terms
- Adolescent, Adult, Analgesics, Double-Blind Method, Drug Synergism, Female, Hot Temperature, Humans, Injections, Intravenous, Male, Middle Aged, Morphine, Pain, Pain Measurement, Dronabinol, Cross-Over Studies
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