Subanalgesic ketamine enhances morphine-induced antinociceptive activity without cortical dysfunction in rats

Abstract

The present results indicate that the morphine-induced analgesic effect is enhanced by a concomitant subanalgesic dose of ketamine without affecting cortical function. Our findings possibly support the clinical notion that low-dose ketamine as an analgesic adjuvant has therapeutic potential to reduce opioid dosage, thereby improving the quality of life in cancer pain patients.

Randomized Controlled Feasibility Trial of Intranasal Ketamine Compared to Intranasal Fentanyl for Analgesia in Children with Suspected Extremity Fractures

“…While ketamine is postulated to have an opioid‐sparing effect by modulating the NMDA and other receptors, there is a paucity of compelling evidence for this effect in children with acute pain. A meta‐analysis by Dahmani et al .…”

Methoxetamine affects brain processing involved in emotional response in rats

“…Similarly, in the hot‐plate test, rats treated i.p. with ketamine 10–20 mg·kg −1 did not change their latency of reaction (Getova and Doncheva, ) and a significant analgesic effect of ketamine occurred only following administration of higher doses of ketamine (25 mg·kg −1 ) (Shikanai et al, ). That MXE induces its antinociceptive effects at doses lower than those classically reported for ketamine could be due to the presence of the methoxy group, which is likely to increase μ‐opioid receptor affinity, and to that of the N‐ ethylamino group that could increase potency of action.…”

Analgesia and Sedation Strategies in Mechanically Ventilated Adults with COVID‐19

“…78 Additional sedation from functional and electrophysiological dissociation of thalamoneocortical and limbic systems and analgesia, comparable to morphine, from land j-receptor agonism aid in ketamine's variable and evolving role in COVID-19 ARDS management. 79,80 Whereas analgesia may be producible at lower ketamine doses (i.e., <0.5 mg/kg/h), dissociative sedation requires higher doses (i.e., 1-5 mg/kg/ h). Deeper sedation and burst suppression may be attained with doses> 5 mg/kg/hour.…”

“…Ketamine, an NMDA receptor antagonist, interferes with ion channel opening and neuron depolarization to produce sedative and analgesic effects. 78 Additional sedation from functional and electrophysiological dissociation of thalamo‐neocortical and limbic systems and analgesia, comparable to morphine, from μ‐ and κ‐receptor agonism aid in ketamine’s variable and evolving role in COVID‐19 ARDS management 79, 80 . Whereas analgesia may be producible at lower ketamine doses (i.e., <0.5 mg/kg/h), dissociative sedation requires higher doses (i.e., 1–5 mg/kg/h).…”