morphine is an opioid drug used to treat acute and chronic pain. morphine can be administered together with cannabinoids to treat some types of pain with a synergistic interaction effect. The interaction can also reduce the tolerance of pain treatment by using a low dose combination of both drugs. More research is needed to optimize the clinical use of this drug combination.
CBD shows a synergistic interaction with morphine only in the acetic acid-stimulated stretching assay (Neelakantan et al., 2015).
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There are some analgesic effects when combining THC with morphine, but more research is needed to find the best dose combination and to improve the time and route of administration depending on the pharmacokinetics of both drugs (Naef et al., 2003). THC shown synergic effects in combination with morphine only in the affective component of pain (Roberts et al., 2006).
Naef, M., Curatolo, M., Petersen-Felix, S., Arendt-Nielsen, L., Zbinden, A., and Brenneisen, R. (2003). The analgesic effect of oral delta-9-tetrahydrocannabinol (THC), morphine, and a THC-morphine combination in healthy subjects under experimental pain conditions: pain 105, 79–88.
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