Recent studies in our laboratory have shown that in mice, low doses of morphine in combination with Delta(9)-tetrahydrocannabinol (Delta(9)-THC) have a similar antinociceptive effect to high doses of morphine alone. After short-term administration of this combination, there is no behavioral tolerance to the opioid. Previous binding studies and Western analyses following chronic morphine exposur...

Opioid abuse is a national epidemic in the United States, where it is estimated that a prescription drug overdose death occurs every 19 minutes. While opioids are highly effective in acute and subacute pain control, their use for treatment of chronic pain is controversial. Chronic opioids use is associated with tolerance, dependency, hyperalgesia. Although there are new strategies and practice ...

Abstract Opioids are one of the effective forms analgesia for acute pain in perioperative period but, with overprescription, have become detrimental to public health. There has been a steady increase opioid consumption and number opioid-related deaths, U.S. government declared epidemic as health emergency. Anesthesiologists responsibility first exposure opioids was during majority cases. Acute ...

BACKGROUND AND OBJECTIVES Low doses of ketamine or isomers are promising possibilities for anesthesia and postoperative analgesia. This study aimed at reviewing major properties of low ketamine doses, which may justify their use in anesthesia and postoperative analgesia. CONTENTS Literature suggests that ketamine induces preemptive and preventive postoperative pain relief, decreasing opioid c...

Opioids are broad spectrum analgesics that may be beneficial to alleviate the intense perception of algesia in patients suffering with pain. They have been one of the most controversial analgesics, in part because of their potential for addiction. Opioids or any currently available analgesic will not provide effective analgesia for every patient with chronic neuropathic pain (NP), but overall o...

Chronic morphine treatment has been shown to produce constitutive activation of mu-opioid receptors, and this transition might contribute to the development of tolerance and dependence. The apparent ability of chronic morphine to increase the spontaneous, agonist-independent activation of mu-opioid receptors may be unique, due to its distinct partial agonist properties of possessing a relativel...

PAIN is “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.” In settings where pain is poorly controlled, patients suffer needlessly and may develop untoward emotional and cognitive responses that negatively affect behavior, rehabilitation, and quality of life. Providing rapid and effective relief of pain remai...

Information regarding opioid tolerance in the pediatric population is limited, and the information for treating pediatric opioid tolerance is extrapolated from the adult population (Shapiro et al. 1995). The majority of the literature on withdrawal syndromes and tolerance comes from the adult literature and is associated with opioidaddicted patients (Collett 1998; Anand and Arnold 1994). Opioid...

Background The role of δ opioid receptors in opioid antinociception and tolerance development is still unclear. In the spinal cord of morphine-tolerant mice δ receptor ligands given intrathecally (i.t.) differently influenced the antinociceptive effect of the μ agonist D-Ala2-methyl-glycinol (DAMGO). The δ1 agonist D-Pen2,5-enkephalin (DPDPE) inhibited, the δ2 agonist deltorphin II did not alte...

There has been increasing recognition of the problem of fatal opioid overdose. This review examines the pharmacological basis of respiratory depression following opioid administration. Respiration is controlled principally through medullary respiratory centres with peripheral input from chemoreceptors and other sources. Opioids produce inhibition at the chemoreceptors via mu opioid receptors an...