BACKGROUND The prevalence, efficacy, and risk for addiction for persons receiving opioids for chronic back pain are unclear. PURPOSE To determine the prevalence of opioid treatment, whether opioid medications are effective, and the prevalence of substance use disorders among patients receiving opioid medications for chronic back pain. DATA SOURCES English-language studies from MEDLINE (1966...

OBJECTIVE There is growing concern of medication misuse and noncompliance among patients with chronic pain prescribed opioids for pain. The aim of this survey was to obtain information from primary care providers (PCPs) about their perception of prescribing opioids for patients with chronic pain. METHODS PCPs were invited to complete a packet of questionnaires about attitudes and concerns abo...

The effects of opioids usually parallel the plasma concentrations but with a temporal shift. This temporal shift differs between opioids. It is small with alfentanil or remifentanil and very long with the active metabolite of morphine, morphine-6-glucuronide (M6G). The mathematical and experimental techniques for modeling these pharmacokineticpharmacodynamic (PK/PD) relationships were developed...

Endogenous opioids target noradrenergic locus ceruleus (LC) neurons and potently inhibit LC activity. Nonetheless, it has been difficult to demonstrate functional regulation of the LC-noradrenergic system by endogenous opioids because of the lack of effect of opiate antagonists. The present findings provide evidence that endogenous opioids regulate LC neuronal activity during the termination of...

Neuromodulators, including transmitters and peptides, modify neuronal excitability. In most neurons, multiple neuromodulator receptors are present on a single cell. Previous work has demonstrated either occlusive or additive effects when two neuromodulators that target the same ion channel are applied together. In this study, we characterize the modulation of Ca2+ and K+ channels in embryonic c...

BACKGROUND To assess the role of transdermal opioids as a front-line approach to moderate to severe cancer pain. METHODS A systematic review of the literature was performed by two authors. An analysis of the level of evidence and risk/benefit ratio was performed for all of the selected trials. A combined analysis of the included studies to assess the level of evidence, risk/benefit ratio and ...

Over 50% of HIV-1/AIDS patients suffer chronic pain. Currently, opioids are the cornerstone medications for treating severe pain in these patients. Ironically, emerging clinical data indicates that repeated use of opiate pain medicines might in fact heighten the chronic pain states in HIV patients. Both laboratory-based and clinical studies strongly suggest that opioids exacerbate the detriment...

Clinical studies comparing the response and side effects of various opioids have not been able to show robust differences between drugs. Hence, recommendations of the regulatory authorities have been driven by costs with a general tendency in many countries to restrict physician's use of opioids to morphine. Although this approach is recognized as cost-effective in most cases there is solid evi...

The objective of this investigation was to characterize the role of complex biophase distribution kinetics in the pharmacokinetic-pharmacodynamic correlation of a wide range of opioids. Following intravenous infusion of morphine, alfentanil, fentanyl, sufentanil, butorphanol and nalbuphine the time course of the EEG effect was determined in conjunction with blood concentrations. Different bioph...

The chronic use of opioids in humans, accompanied by the development of tolerance, is a dangerous phenomenon in its own right. However, chronic opioid use is often made more dangerous by the coconsumption of other substances. It has been observed that the blood level of opioids in postmortem analyses of addicts, who consumed ethanol along with the opioid, was much less than that observed in ind...