Major depressive disorder (MDD) continues to pose a major therapeutic challenge due to its clinical heterogeneity. This chapter looks at the development of antidepressant treatments, starting with early interventions such as electroconvulsive therapy (ECT), monoamine oxidase inhibitors (MAOIs) and tricyclic antidepressants (TCAs). Although these treatments t...
IntroductionExtant literature suggests that anhedonia, defined as a loss of the ability to feel pleasure or interest, is subserved by dysregulation of reward processing in the central nervous system. Dextromethorphan (DXM), an uncompetitive N-Methyl-d-Aspartate (NMDA) receptor antagonist and sigma-1 (σ1) receptor agonist, is a glutamatergic modulator with an...
The stresses of the Coronavirus Disease of 2019 (COVID-19) pandemic highlighted the burden of psychiatric disorders within the pediatric population, revealing a pre-existing need for rapid-onset therapies that have since driven efforts to expand effective therapeutic interventions. In this narrative review, we utilized the Preferred Reporting Items for Syste...
Major depressive disorder is a debilitating condition, with many patients unresponsive to conventional monoaminergic antidepressants. Rapid-acting antidepressants such as ketamine and psilocybin offer promising alternatives, relieving symptoms within hours. Ketamine, an NMDA receptor antagonist, and psilocybin, a serotonergic psychedelic primarily targeting ...
The full therapeutic potential of serotonergic psychedelics (SP) in treating neuropsychiatric disorders, such as depression and schizophrenia, is limited by possible adverse effects, including perceptual disturbances and psychosis, which require administration in controlled clinical environments. This study investigates the synergistic benefits of combining ...
Modern research data suggest a therapeutic role for serotonergic psychedelics in depression and other neuropsychiatric disorders, although psychotomimetic effects may limit their widespread utilization. Serotonergic psychedelics enhance neuroplasticity via serotonin 2 A receptors (5HT2AR) activation and complex serotonergic-glutamatergic interactions involvi...
Rationale: N-methyl-D-aspartate receptor-mediated dissociatives and serotonergic hallucinogens are being increasingly used in therapeutic interventions that involve nonordinary states of consciousness and may represent a unique mental health paradigm wherein pharmacologically induced experiences are conducive to psychological well-being. Objective: The aim o...
Major depressive disorder (MDD) is a chronic relapsing psychiatric disorder. Conventional antidepressants usually require several weeks of continuous administration to exert clinically significant therapeutic effects, while about two-thirds of the patients are prone to relapse of symptoms or are completely ineffective in antidepressant treatment. The recent ...
Since the dawn of civilization, ancient cultures have utilized hallucinogens from plants and fungi in the context of religious and healing practices. Recently, their use has expanded to other cultures. Hallucinogens are natural or synthetic substances that alter the perception of reality at nontoxic doses, producing intense psychological and physiological ef...
IntroductionMajor depressive disorder remains a prevalent world-wide health problem. Currently available antidepressant medications take weeks of dosing, do not produce antidepressant response in all patients, and have undesirable ancillary effects.Areas coveredThe present opinion piece focuses on the major inroads to the creation of new antidepressants. The...
Rapid-acting antidepressants disprove the dogma that antidepressants need several weeks to become clinically effective. Ketamine, the prototype of a rapid-acting antidepressant, is an N-methyl-D-aspartate (NMDA) receptor blocking agent. A single i.v. application of ketamine induces rapid changes in glutamatergic neurotransmitter systems, leading to preferent...
Hallucinogens constitute a unique class of substances that cause changes in the user's thoughts, perceptions, and mood through various mechanisms of action. Although the serotonergic hallucinogens such as lysergic acid diethylamide, psilocybin, and N,N-dimethyltryptamine have been termed the classical hallucinogens, many hallucinogens elicit their actions th...
Mounting evidence suggests safety and efficacy of psychedelic compounds as potential novel therapeutics in psychiatry. Ketamine has been approved by the Food and Drug Administration in a new class of antidepressants, and 3,4-methylenedioxymethamphetamine (MDMA) is undergoing phase III clinical trials for post-traumatic stress disorder. Psilocybin and lysergi...
Conventional antidepressants (biogenic amine mechanisms) are not fully efficacious (e.g., symptoms remain after treatment, not all patients respond), produce effects only after weeks of daily dosing, and do not impact all disease symptoms. In contrast, a new class of antidepressants has been emerging since 2006 that has demonstrated rapid onset, large effect...
Depression and anxiety are psychiatric diagnoses commonly associated with low quality of life and low percentage of responsiveness by patients treated with currently available drugs. Thus, research into alternative compounds to treat these disorders is essential to guarantee a patient's remission. The last decade has witnessed a revamped interest for the app...
Background and objectives: Considering the increasing prevalence of depression, many studies are launched to investigate new antidepressant treatments. The present research has shown how psilocybin as an active compound of Psilocybe cubensis (Earle) Singer extract (PCE) can change the parameters related to depression and anxiety in animal models. Both seroto...
Recent clinical trials suggest that 3 single biological treatments have effects that persist. Based on research showing that the muscles involved in facial expressions can feed back to influence mood, a single trial diminishing glabella frown lines with botulinum toxin demonstrated a significant antidepressant effect for 16 weeks. Based primarily on research...
RationaleBoth glutamate and serotonin (5-HT) play a key role in the pathophysiology of emotional biases. Recent studies indicate that the glutamate N-methyl-D-aspartate (NMDA) receptor antagonist ketamine and the 5-HT receptor agonist psilocybin are implicated in emotion processing. However, as yet, no study has systematically compared their contribution to ...
Psychotomimetics like the N-methyl-D-aspartate receptor (NMDAR) antagonist ketamine and the 5-hydroxytryptamine2A receptor (5-HT(2A)R) agonist psilocybin induce psychotic symptoms in healthy volunteers that resemble those of schizophrenia. Recent theories of psychosis posit that aberrant encoding of prediction errors (PE) may underlie the expression of psych...
RationaleMany studies have reported deficits of mismatch negativity (MMN) in schizophrenic patients. Pharmacological challenges with hallucinogens in healthy humans are used as models for psychotic states. Previous studies reported a significant reduction of MMN after ketamine (N-methyl-D-aspartate acid [NMDA] antagonist model) but not after psilocybin (5HT2...
