Neuroplasticity refers to the ability of the brain to modify synaptic connections and reorganize neural circuits, underpinning cognitive function, emotional regulation, and recovery from injury. Recen Show more
Neuroplasticity refers to the ability of the brain to modify synaptic connections and reorganize neural circuits, underpinning cognitive function, emotional regulation, and recovery from injury. Recent advances have redefined adult neuroplasticity as more dynamic and therapeutically accessible than previously thought, spurring investigation into pharmacological interventions that can augment these adaptive processes. This review dissects current evidence for drug strategies targeting synaptic modulators (NMDA, AMPA, and GABA receptors), neuropeptide systems (including BDNF, oxytocin, vasopressin), and psychedelic compounds (psilocybin, LSD, ketamine), integrating insights from cellular, preclinical, and clinical studies. We detail how these agents modulate molecular pathways governing synaptic transmission, dendritic remodeling, and gene expression linked to neuronal growth and resilience. Highlighted findings include the rapid-acting antidepressant effects of NMDA antagonists, the structural and functional reorganization induced by classic psychedelics via 5-HT2A receptor activation, and the neurorestorative roles of neuropeptides in synaptic and network adaptation. Alongside these advances, we critically address safety, ethical considerations, and the risk of maladaptive plasticity, underscoring the importance of dosing, patient selection, and controlled therapeutic environments. Non-hallucinogenic neuroplastogens and combinatorial approaches that are still emerging offer new avenues to fine-tune plasticity with an improved safety profile. The collective evidence positions neuroplasticity-targeting pharmacology as a promising and complex frontier for the treatment of neuropsychiatric and neurodegenerative disorders in adulthood. Show less
The global rise in mental health conditions has prompted interest in interventions that act beyond conventional psychopharmacology. Psychobiotics, broadly understood as live microorganisms or microbe- Show more
The global rise in mental health conditions has prompted interest in interventions that act beyond conventional psychopharmacology. Psychobiotics, broadly understood as live microorganisms or microbe-derived products that interact with the microbiota-gut-brain axis, have been suggested to exert neuroactive effects through neural, immune, endocrine and metabolic routes. This narrative review synthesizes recent preclinical, mechanistic and early clinical observations. Experimental studies show that selected strains can modulate cytokine signalling, influence stress-responsive systems such as the hypothalamic-pituitary-adrenal axis, and support synaptic plasticity via factors such as brain-derived neurotrophic factor. A limited number of human trials using well-characterized Lactobacillus and Bifidobacterium strains have reported improvements in affective and stress-related outcomes, but these effects are generally small to moderate, more apparent in adjunctive than stand-alone use, and dependent on strain, dose, population and intervention length (typically 4-12 weeks). Evidence on neurodevelopmental conditions (e.g., autism spectrum disorder, attention-deficit/hyperactivity disorder) remains preliminary, based on small and heterogeneous samples. Across studies, key constraints include methodological heterogeneity, incomplete strain-level reporting, and gaps in mechanistic resolution that make it difficult to link microbial shifts to psychiatric benefit. Emerging microbiome- and metabolomics-informed approaches may help identify likely responders and improve translational precision, but they are not yet ready for routine clinical application. Overall, psychobiotics should currently be viewed as a promising adjunct within integrative mental health care, warranting larger, standardized trials with clearly defined strains, doses and mechanistic endpoints. Show less