Although recreational inhalation of nitrous oxide (N 2 O) often causes acute, severe symptoms–most notably spinal cord degeneration due to functional vitamin B 12 inactivation–diagnosis remains challenging. It is frequently missed by frontline providers because multi-system involvement complicates the differential diagnosis, which is further obscured by internet-guided harm reduction. This...
Treatment-resistant depression (TRD) remains a formidable challenge in psychiatry, with nearly one-third of patients with major depressive disorder (MDD) failing to respond adequately to first-line pharmacological treatments. Pathophysiology in MDD has highlighted the N-methyl-D-aspartate (NMDA) glutamatergic system as a promising therapeutic target. In 2022, the US Food and Drug Administration...
Objective: To synthesize the neurobiological basis of brain-resetting effects of psilocybin and identify neuroimaging correlates of psilocybin response in depressed patients. Data Sources: MEDLINE(R), Embase, APA PsycINFO, Cochrane, and CINAHL were systematically searched on June 3, 2022, with no date restrictions using the following string: (psilocybin) AND (psychedelics) AND (MRI) OR (fMRI))...
For the last 70 years, we did not move beyond the monoamine hypothesis of depression until the approval of the S-enantiomer of ketamine, an N-methyl-D-aspartate (NMDA) receptor blocker and the first non-monoaminergic antidepressant characterized by rapid antidepressant and antisuicidal effects. A similar profile has been reported with another NMDA receptor antagonist, dextromethorphan, which...