Articles: opioid.
-
To examine trends in opioid poisonings and adverse effects in Washington (WA) State and nationally. ⋯ Many poisonings and adverse effects occurred in patients without high dose or long-term opioid therapy, suggesting that opioid dosing and duration guidelines may not be sufficient to reduce morbidity related to prescription opioid use.
-
The ventrolateral periaqueductal gray (vlPAG) contributes to morphine antinociception and tolerance. Chronic inflammatory pain causes changes within the PAG that are expected to enhance morphine tolerance. This hypothesis was tested by assessing antinociception and tolerance following repeated microinjections of morphine into the vlPAG of rats with chronic inflammatory pain. Microinjection of morphine into the vlPAG reversed the allodynia caused by intraplantar administration of complete Freund's adjuvant and produced antinociception on the hot plate test. Although there was a gradual decrease in morphine antinociception with repeated testing, there was no evidence of tolerance when morphine- and saline-treated rats with hind paw inflammation were tested with cumulative doses of morphine. In contrast, repeated morphine injections into the vlPAG caused a rightward shift in the morphine dose-response curve in rats without hind paw inflammation, as would be expected with the development of tolerance. The lack of tolerance in complete Freund's adjuvant-treated rats was evident whether rats were exposed to repeated behavioral testing or not (experiment 2) and whether they were treated with 4 or 8 prior microinjections of morphine into the vlPAG (experiment 3). These data demonstrate that chronic inflammatory pain does not disrupt the antinociceptive effect of microinjecting morphine into the vlPAG, but it does disrupt the development of tolerance. ⋯ The present data show that induction of chronic inflammatory pain does not disrupt the antinociceptive effect of microinjecting morphine into the vlPAG, but it does attenuate the development of tolerance. This finding indicates that tolerance to opioids in rats with inflammatory pain is mediated by structures other than the vlPAG.
-
Available evidence to help guide efficacious nonsteroidal anti-inflammatory drug and opioid analgesic prescribing will be reviewed. ⋯ The available evidence can guide but cannot provide any prescriber with absolute knowledge regarding outcome for these frequently prescribed and potentially dangerous agents. Knowledge of the available evidence and application of such to our patients on an individualized basis hopefully will help to optimize therapeutic goals and minimize harms.
-
Pain has sensory-discriminative and emotional-affective dimensions. Recent studies show that the affective component can be assessed with a conditioned place avoidance (CPA) test. We hypothesized that systemic morphine before a post-conditioning test would more potently attenuate the affective aspect compared to the sensory component and that [d-Ala2-N-Me-Phe4, Gly-ol5]-enkephalin (DAMGO), a μ-selective opioid receptor agonist, injected into the central nucleus of the amygdala (CeA) would reduce established CPA. ⋯ I.t. morphine did not inhibit the display of CPA but significantly increased PWL, suppressing hyperalgesia (P<0.05). Intra-CeA DAMGO significantly inhibited the display of CPA compared to saline (P<0.05) but had no effect on PWL. The data demonstrate that morphine attenuates the affective component more powerfully than it does the sensory and suggests that the sensory and the emotional-affective dimensions are underpinned by different mechanisms.
-
With greater scrutiny on primary care providers' (PCPs) approaches to chronic pain management, more research is needed to clarify how concerns and uncertainties about opioid therapy affect the ways both patients with chronic pain and PCPs experience primary care interactions. The goal of this qualitative study was to develop a better understanding of the respective experiences, perceptions, and challenges that patients with chronic pain and PCPs face communicating with each other about pain management. ⋯ Competing demands of primary care practice, differing beliefs about pain, and uncertainties about the appropriate place of opioid therapy in chronic pain management likely contributed to the identified tensions. Several clinical communication strategies to help PCPs mitigate and manage pain-related tensions are discussed.