A bibliometric analysis of 710 publications from 2004 to October 2023 reveals growing research interest in psychedelics as treatments for depression. The analysis maps annual publication trends, authorship, countries, institutions, journals, and keywords to visualize emerging frontiers and influential factors. The authors assert that regulation of psychedelic drugs is necessary but should not impede scientific progress.
Opioid-induced hyperalgesia (OIH) is a complication of pain treatment where opioids paradoxically increase pain sensitivity. Using a mouse model, about 60% of mice developed OIH after three days of morphine, shown by abnormal movement and anxiety-like behaviors. Mice whose gut microbiota were eliminated with antibiotics did not develop hyperalgesia, but those receiving fecal transplants from OIH mice did. S-ketamine, but not R-ketamine, prevented OIH. Gut microbiota analysis revealed increased Enterobacteriaceae in OIH-susceptible mice, which decreased after S-ketamine treatment. The findings suggest S-ketamine alleviates morphine-induced OIH by reducing gut Enterobacteriaceae levels.