BACKGROUND Opioid misuse and abuse occurring in association with the treatment of chronic non-cancer pain are not new phenomena, but their increasing prevalence in recent years is unprecedented. Advancements in pharmaceutical technologies have provided opioid-related drugs, which lack the pure mu agonist activity characteristic of the typical opioid congeners. This absent or altered mu receptor...

The G protein-coupled receptor (GPCR) µ-opioid (µOR) is one of several drug targets commercially available pain therapeutics. Various opioid drugs, such as morphines, have been associated with numerous substance abuse-related deaths around the world. Targeting allosteric sites can preclude this undesirable side effect. In addition, understanding underlying mechanism ligands in µOR highly sought...

Cocaine and heroin often are abused by self-administering the drugs in combination as a "speedball". We evaluated the extent to which intrinsic efficacy at the mu-opioid receptor influences combined cocaine-opioid self-administration and used the behavioral economic model termed "labor supply" to quantitatively evaluate the reinforcing effects of cocaine-opioid combinations. Rhesus monkeys (n =...

Chronic treatment of pain with opiate drugs can lead to analgesic tolerance and drug dependence. Although all opiate drugs can promote tolerance and dependence in practice, the severity of those unwanted side effects differs depending on the drug used. Although each opiate drug has its own unique set of pharmacological profiles, methadone is the only clinically used opioid drug that produces su...

Received: December 20, 2016 Revised: February 14, 2017 Accepted: February 17, 2017 Abstract: Background: Pruritus is a very disturbing secondary effect that appears after epidural or intrathecal administration of opioid drugs, especially in the management of postoperative pain. It is induced by the activation of mu opioid receptors and it can often be even more unpleasant than the pain being tr...

Chronic pain syndrome developing in patients with oncological diseases significantly decreases their quality of life which makes effective integrative analgetic therapy a pressing issue. Currently, drugs various pharmaceutical groups are used for management and administered subsequentially accordance the intensity visual analogue scale. For moderate severe syndrome, opioid analgesics have side ...

Opioid drugs are potent modulators of many physiological and psychological processes. When given acutely, they can elicit the signature responses of euphoria and analgesia that societies have coveted for centuries. Repeated, or chronic, use of opioids induces adaptive or allostatic changes that modify neuronal circuitry and create an altered normality - the "drug-dependent" state. This state, a...

Anabolic-androgenic steroids (AAS) are drugs of abuse. They are taken in large quantities by athletes and others to increase performance, with negative health consequences. As a result, in 1991 testosterone and related AAS were declared controlled substances. However, the relative abuse and dependence liability of AAS have not been fully characterized. In humans, it is difficult to separate the...