Usefulness of the dopamine system-stabilizer aripiprazole for reducing morphine-induced emesis

Treatment of Pain in Ferrets

Ferrets often require pain management as part of comprehensive veterinary care. Recognition and objective quantification of pain, such as the ferret grimace scale, are the first steps of an analgesic plan. As in other species, a multimodal approach to pain management is preferred, which includes combining analgesic drugs of multiple classes and/or techniques to affect different areas of the pain pathway. This article reviews the current published literature on analgesic medications in domestic ferrets, including specific drugs, doses, dosing intervals, and routes of administration.

Chronic Atypical Antipsychotic Use Is Associated With Reduced Need for Postoperative Nausea and Vomiting Rescue in the Postanesthesia Care Unit: A Propensity-Matched Retrospective Observational Study

BACKGROUND

Atypical antipsychotics are efficacious for chemoprophylaxis against chemotherapy-induced nausea and vomiting, but perioperative investigations have been scant. We sought to examine the association between chronic atypical antipsychotic therapy and the likelihood of postoperative nausea and vomiting.

METHODS

In this single-center, propensity-matched, retrospective, observational study, elective noncardiac surgical cases from January 2014 to December 2017 were examined with regard to the primary outcome of rescue antiemetic administration in the postanesthesia care unit as a measure of postoperative nausea and vomiting. Chronic administration of olanzapine, aripiprazole, and risperidone was the exposure of interest. Other independent variables included outpatient antiemetics, modified Apfel score, age, American Society of Anesthesiologists physical status score, case length, and exposures to emetogenic and chemoprophylactic agents. Logistic regression was performed using case-level data. Conditional logistic regression was performed after 1:2 propensity matching, sampling without replacement. Monte Carlo simulation was performed to compute the mean patient-level treatment effect on the treated.

RESULTS

Of 13,660 cases, 154 cases with patients receiving atypical antipsychotics were matched against 308 cases without, representing 115 and 273 unique patients, respectively. In a well-balanced cohort, the mean patient-level odds of being administered rescue antiemetic was lower for patients chronically taking the 3 atypical antipsychotics under consideration as compared to those not on atypical antipsychotics, with an odds ratio of 0.29 (95% CI, 0.11-0.75; P = .015).

CONCLUSIONS

Chronic atypical antipsychotic therapy is associated with reduced risk of postanesthesia care unit antiemetic administration. These findings support the need for prospective studies to establish the safety and efficacy of postoperative nausea and vomiting chemoprophylaxis with these agents.

In vitro and in vivo anti-tumor effects of brexpiprazole, a newly-developed serotonin-dopamine activity modulator with an improved safety profile

From the perspective of psycho-oncology, antipsychotics are widely used for patients with cancer. Although some antipsychotic drugs have anti-tumor effects, these antipsychotic drugs are not applicable for cancer patients because of their severe side effects. Brexpiprazole, a novel serotonin-dopamine modulator with an improved side effect profile, was developed as a drug that is structurally and pharmacologically related to aripiprazole, which was reported to have anti-cancer effects. However, it remains unknown whether brexpiprazole has anti-cancer effects. In this study, we examined whether brexpiprazole has anti-tumor effects in cancer cells and cancer stem cells (CSCs) of glioblastoma, pancreatic cancer, and lung cancer. Brexpiprazole suppressed cell growth and induced cell death in the cancer cells and the CSCs, and decreased the CSC properties of the CSCs. Brexpiprazole did not exert any cytotoxic effects on non-cancer cells at the anti-cancer effect-inducing concentration. In the cancer cells and the CSCs, brexpiprazole reduced the expression of survivin, an anti-apoptotic protein, whose reduction sensitizes tumor cells to chemotherapeutic reagents. In the preclinical model in which pancreatic CSCs were subcutaneously implanted into nude mice, brexpiprazole suppressed tumor growth, in addition to reducing the expression of Sox2, a marker for CSCs, and survivin. This suggests that brexpiprazole is a promising antipsychotic drug with anti-tumor effects and an improved safety profile.

Opioid induced nausea and vomiting

Opioids are broad spectrum analgesics that are an integral part of the therapeutic armamentarium to combat pain in the palliative care population. Unfortunately, among the adverse effects of opioids that may be experienced along with analgesia is nausea, vomiting, and/or retching. Although it is conceivable that in the future, using combination agents (opioids combined with agents which may nullify emetic effects), currently nausea/vomiting remains a significant issue for certain patients. However, there exists potential current strategies that may be useful in efforts to diminish the frequency and/or intensity of opioid-induced nausea/vomiting (OINV).

Effects of dronabinol on morphine-induced dopamine-related behavioral effects in animals

The present study examined the effects of dronabinol, a United States FDA-approved synthetic cannabinoid receptor agonist, on morphine (a prototypic μ-opioid receptor agonist)-induced dopamine-related behaviors in animals. Dronabinol suppressed the rewarding effects of morphine in rats and its emetic effects in ferrets. Furthermore, the morphine-induced increase in dopamine release from the nucleus accumbens was significantly attenuated by dronabinol, which indicated that the suppressive effects of dronabinol on morphine-induced behaviors are at least in part mediated by regulation of the dopaminergic system. Since cannabinoid receptor agonists have been shown to enhance the antinociceptive effects of morphine, the use of dronabinol as an adjuvant could be useful for preventing the adverse effects of μ-opioid receptor agonists when used to control pain.

Pain management in ferrets

The growing popularity of ferrets as pets has created the demand for advanced veterinary care for these patients. Pain is associated with a broad range of conditions, including acute or chronic inflammatory disease, neoplasia, and trauma, as well as iatrogenic causes, such as surgery and diagnostic procedures. Effective pain management requires knowledge and skills to assess pain, good understanding of the pathophysiology of pain, and general knowledge of pharmacologic and pharmacodynamic principles. Unfortunately, scientific studies on efficacy, pharmacokinetics, pharmacodynamics, and safety of analgesic drugs in the ferret are limited. However, basic rules on the treatment of pain and mechanisms of action, safety, and efficacy of analgesic drugs in other species can be adapted and applied to pain management in ferrets. This article aims to make an inventory of what is known on the recognition of pain in ferrets, what analgesic drugs are currently used in ferrets, and how they can be adopted in a patient-orientated pain management plan to provide effective pain relief while reducing and monitoring for unwanted side effects.

Endogenous opiates and behavior: 2007

This paper is the thirtieth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2007 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia; stress and social status; tolerance and dependence; learning and memory; eating and drinking; alcohol and drugs of abuse; sexual activity and hormones, pregnancy, development and endocrinology; mental illness and mood; seizures and neurologic disorders; electrical-related activity and neurophysiology; general activity and locomotion; gastrointestinal, renal and hepatic functions; cardiovascular responses; respiration and thermoregulation; and immunological responses.