The pharmacological effects of the opioid analgesics are derived from their complex interactions with three opioid receptor types (mu, delta, and kappa; morphine is an agonist at the mu opioid receptor). These receptors are found in the periphery, at presynaptic and postsynaptic sites in the spinal cord dorsal horn, and in the brain stem, thalamus, and cortex, in what constitutes the ascending ...

INTRODUCTION In North America, drug overdose deaths are reaching unprecedented levels, largely driven by increasing prescription opioid-related deaths. Despite the development of several opioid guidelines, prescribing behaviours still contribute to poor patient outcomes and societal harm. Factors at the provider and system level may hinder or facilitate the application of evidence-based guideli...

conclusions a modified tool to assess methadone treatment response serves to identify patients at high-risk for relapse at a minimal cost, as well as evaluate the relevant physical and psycho-social domains affecting opioid-dependent patients. the great will serve as a useful adjunct to regular clinical assessments, allowing clinicians and researchers to properly assess opioid addiction patient...

The Neuropeptide S system, consisting of the 20-amino acid peptide neuropeptide S (NPS) and its G-protein coupled receptor (NPSR), modulates arousal, wakefulness, anxiety, and fear-extinction in mice. In addition, recent evidence indicates that the NPS system attenuates stress-dependent impairment of fear extinction, and that NPS-expressing neurons in close proximity to the locus coeruleus regi...

OBJECTIVES To estimate the frequency and characteristics of opioid prescribing by multiple providers in Medicare and the association with hospital admissions related to opioid use. DESIGN Retrospective cohort study. SETTING Database of prescription drugs and medical claims in 20% random sample of Medicare beneficiaries in 2010. PARTICIPANTS 1,808,355 Medicare beneficiaries who filled at l...

CONTEXT The endogenous opioid system and opioid mu receptors (mu-receptors) are known to interface environmental events, positive (eg, relevant emotional stimuli) and negative (eg, stressors), with pertinent behavioral responses and to regulate motivated behavior. OBJECTIVE To examine the degree to which trait impulsiveness (the tendency to act on cravings and urges rather than to delay grati...

Loperamide is an over-the-counter antidiarrheal with opioid-receptor agonist properties. Recommended over-the-counter doses (range = 2-8 mg daily) do not produce opioid effects in the central nervous system because of poor oral bioavailability and P-glycoprotein efflux* of the medication (1); recent reports suggest that large doses (50-300 mg) of loperamide produce euphoria, central nervous sys...

The present study investigated the effects of intra-dentate gyrus microinjection of naloxone (an opioid antagonist) and thioperamide (an antagonist of histamine H3 receptors) in the formalin test in rats. Subcutaneous injection of formalin (50 μl, 2.5 %) in the ventral surface of right hind paw produced a biphasic pattern (first phase: 0-5 min and second phase: 15 - 60 min) of licking/biting an...

Background: Several studies have shown that the ethanol-derived metabolite salsolinol (SAL) can activate the mesolimbic system, suggesting that SAL is the active molecule mediating the rewarding effects of ethanol. In vitro and in vivo studies suggest that SAL exerts its action on neuron excitability through a mechanism involving opioid neurotransmission. However, there is no direct pharmacolog...

Chronic pain is a prevalent and debilitating condition, conveying immense human burden. Suffering from chronic pain is not only caused by painful symptomatology, but also through a wide range of psychopathological and physical consequences, including depression and anxiety disorders, impaired sleep and cognition, cardiovascular morbidity and impaired sexual function, all contributing to diminis...