Can Src protein tyrosine kinase inhibitors be combined with opioid analgesics? Src and opioid-induced tolerance, hyperalgesia and addiction

The clinical application of opioids may be accompanied by a series of adverse consequences, such as opioid tolerance, opioid-induced hyperalgesia, opioid dependence or addiction. In view of this issue, clinicians are faced with the dilemma of treating various types of pain with or without opioids. In this review, we discuss that Src protein tyrosine kinase plays an important role in these adverse consequences, and Src inhibitors can solve these problems well. Therefore, Src inhibitors have the potential to be used in combination with opioids to achieve synergy. How to combine them together to maximize the analgesic effect while avoiding unnecessary trouble provides a topic for follow-up research.

Endogenous opiates and behavior: 2017

This paper is the fortieth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2017 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Effect of dexmedetomidine anesthesia on perioperative levels of TNF-α and IL-6 in patients with ovarian cancer

Effect of continuous use of dexmedetomidine during general anesthesia on perioperative levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in patients undergoing radical resection of ovarian cancer was investigated. The initial treatment of ovarian cancer is mainly radical surgery. Most patients with ovarian cancer radical surgery can achieve good results, but the use of improper anesthetic drugs in radical surgery can easily lead to unstable patient vital signs. Therefore, the selection of appropriate anesthetic drugs has become the key to radical ovarian cancer surgery. There are few reports on the use of dexmedetomidine in anesthesia for ovarian cancer radical surgery. This study was performed to retrospectively analyze the case data of patients undergoing laparoscopic ovarian cancer radical surgery, and to compare the hemodynamics of dexmedetomidine anesthesia with midazolam anesthesia and the concentrations of TNF-α and IL-6, to provide reference for clinical implementation of ovarian cancer radical surgery. The hemodynamics of patients in the dexmedetomidine group were stable compared with the midazolam group. Serum TNF-α and IL-6 levels were significantly lower in the dexmedetomidine group than that in the midazolam group. If dexmedetomidine were continuously used during general anesthesia, the perioperative serum levels of TNF-α and IL-6 could be effectively reduced in patients undergoing radical resection of ovarian cancer, and the perioperative stress response was suppressed.

Prolonged therapy with the anticonvulsant carbamazepine leads to increased plasma clearance of fentanyl

OBJECTIVES

Fentanyl is a potent analgesic that accounts for an increasing number of overdose deaths in the United States. This study tested whether altered pharmacokinetics plays a pivotal role in the increased fentanyl dose requirements in patients receiving the enzyme-inducing anticonvulsant, carbamazepine.

METHODS

Neurosurgical patients receiving carbamazepine for >6 weeks (N = 11) or no carbamazepine (N = 6, controls) received a single bolus dose of fentanyl (200 μg) intravenously. Plasma was collected before and for up to 9 h after the bolus. Fentanyl concentrations were measured using liquid chromatography-mass spectrometry. Pharmacokinetic variables were derived from plasma concentration-time curves best fitted to a two-compartment model.

KEY FINDINGS

Fentanyl clearance was significantly higher in the carbamazepine group compared to controls (mean ± SD: 20.1 ± 6.8 vs 13.2 ± 4.8 ml/min per kg, P < 0.05), and area under the plasma concentration curve (AUC) was significantly lower (150 ± 65 vs 233 ± 70 ng/ml × min, P < 0.02). Volume of distribution was larger in the carbamazepine group, but the difference was not statistically significant (5.4 ± 3.1 vs 3.6 ± 1.2 l/kg, P > 0.15). The terminal elimination half-life did not differ between the two groups.

CONCLUSIONS

Chronic carbamazepine therapy leads to increased fentanyl clearance and decreased AUC, which may result in decreased duration of therapeutic plasma concentrations of fentanyl and an increased dose requirement. Assuming that carbamazepine does not change fentanyl pharmacodynamics, patients on chronic carbamazepine therapy may require more frequent or higher fentanyl doses to maintain therapeutic plasma concentrations.