Brain Sciences
March 16, 2018
Giovanni Martinotti, Rita Santacroce, Mauro Pettorruso et al.
171 citations
Hallucinogen Persisting Perception Disorder (HPPD) is a rare condition linked to hallucinogenic drug use, often diagnosed in individuals with prior psychological issues or substance misuse, but it can occur after a single exposure. This review of 45 original studies examines proposed etiologies, the hallucinogens involved, clinical features of HPPD types I and II, psychiatric comorbidities, and available or potential treatments. The findings suggest that HPPD remains poorly understood, with limited therapeutic options, highlighting the need for further research.
Brain Sciences
June 27, 2021
Giovanni Martinotti, Stefania Chiappini, Mauro Pettorruso et al.
114 citations
Ketamine and esketamine, N-methyl-D-aspartate receptor antagonists, show promise for treating obsessive-compulsive disorder (OCD), eating disorders, and substance use disorders, which share features like obsessive thoughts and compulsive behaviors. A review of literature up to April 2021, following PRISMA guidelines, found that while small studies indicate remarkable results for treatment-resistant depression, PTSD, and OCD, solid evidence for benefits in OCD spectrum and addiction is still lacking. The use is supported by glutamatergic neurotransmission dysregulation. Preliminary data are optimistic, but further studies are needed to clarify unknowns and long-term effectiveness.
CNS Spectrums
June 25, 2020
Giovanni Martinotti, Luisa de Risio, Chiara Vannini et al.
102 citations
About 25% of first-episode psychoses are substance-induced. The DSM-5 definition assumes symptoms are transient and disappear after sustained abstinence, but this does not account for persistent cases. A new diagnostic framework is needed to differentiate comorbid conditions from substance-related psychoses. The authors propose a novel clinical entity called substance-related exogenous psychosis (SREP), covering both transient and persistent psychoses linked to substance use. SREP is distinct from schizophrenia, characterized by altered consciousness, persecutory delusions, visual and cenesthetic hallucinations, impulsivity, psychomotor agitation, affective and negative symptoms, a pervasive feeling of unreality, and intact insight. Delusions are secondary to abnormal perception from a 'sensorialization' of the world. Longitudinal studies are needed to validate this category.
Bipolar Disorders
January 13, 2023
Giovanni Martinotti, Bernardo Dell’osso, Giorgio Di Lorenzo et al.
72 citations
Esketamine nasal spray reduced depressive symptoms in people with treatment-resistant bipolar depression as effectively as in those with unipolar treatment-resistant depression, with no significant differences in response or remission rates after one and three months. The treatment also showed greater anxiety-reducing effects in the bipolar group. No treatment-emergent affective switch occurred, supporting the safety and tolerability of esketamine for bipolar treatment-resistant depression.
Psychiatry Research
July 29, 2023
Mauro Pettorruso, Roberto Guidotti, Giacomo D’andrea et al.
56 citations
Machine learning models predicted which patients with treatment-resistant depression would respond to esketamine nasal spray. In a retrospective study of 149 patients, three random forest classifiers achieved 68.53% accuracy for response at one month and 66.26% at three months, and 68.60% accuracy for remission at three months. Features such as severe anhedonia, anxious distress, mixed symptoms, and bipolarity positively predicted response and remission, while benzodiazepine use and depression severity were linked to delayed responses. The findings suggest machine learning may aid personalized treatment decisions for treatment-resistant depression.
Experimental neurology
May 1, 2021
Fabrizio Schifano, Stefania Chiappini, Andrea Miuli et al.
49 citations
Several new psychoactive substances (NPS) can trigger serotonin syndrome, a dangerous condition of excessive serotonin activity marked by altered mental status, neuromuscular effects, and autonomic hyperactivity. A systematic review of three retrospective studies, two case series, and five case reports identified implicated substances including psychedelic phenethylamines (2C-I, 25I-NBOMe, 5-IT) and synthetic cathinones (mephedrone, MDPV, methylone, butylone, NRG3, AMT, MXP), as well as the antidepressant bupropion when misused at high doses or combined with other serotonergic drugs. Most substances were taken orally, though nasal insufflation and sublingual administration occurred. Psychiatric history was negative for most subjects. Clinicians should recognize NPS risks and diagnostic challenges due to undetectability in routine drug screenings.
European Neuropsychopharmacology
May 4, 2023
Stefania Chiappini, Giacomo D’andrea, Sergio De Filippis et al.
48 citations
Esketamine nasal spray reduces depression symptoms in patients with treatment-resistant depression who also have a substance use disorder. In 26 patients followed for three months, Montgomery-Asberg depression rating scale scores decreased significantly from baseline to one month and from one to three months. Side effects occurred in 73% of patients, most commonly dissociative symptoms and sedation, but none led to lasting harm and no abuse or misuse of the medication was reported. The findings suggest esketamine is effective and safe in this population, though the study is limited by its small sample and short follow-up.
American Journal of Geriatric Psychiatry
July 8, 2023
Giacomo D’andrea, Stefania Chiappini, Roger S. McIntyre et al.
36 citations
Esketamine nasal spray (ESK-NS) shows preliminary effectiveness for treatment-resistant depression in adults aged 65 and older, with 53.3% of participants responding (MADRS score reduced by at least 50%) and 33.33% achieving remission (MADRS below 10) after three months. Common adverse effects included dizziness (50%), dissociation (33.3%), sedation (30%), and hypertension (13.33%). Twenty percent of participants discontinued treatment. These findings, from a post-hoc analysis of 30 older adults, suggest ESK-NS can be effective but is associated with high rates of treatment-emergent adverse events, most of which did not require stopping treatment.
Current Neuropharmacology
October 20, 2022
Alessio Mosca, Stefania Chiappini, Andrea Miuli et al.
30 citations
Ibogaine and noribogaine, psychedelic substances from plants of the Apocynaceae family, show some efficacy in treating substance use disorders, particularly opiate detoxification. However, their use carries concerning risks of cardiotoxicity and mortality. A meta-analysis of side effects found a significant risk of developing headaches after treatment. The evidence, drawn from case reports, randomized controlled trials, open-label studies, surveys, and observational studies, remains unclear on overall efficacy and toxicity. Further research is needed to evaluate therapeutic benefits and safety.
Current neuropharmacology
January 1, 2025
Gianluca Rosso, Giacomo d'Andrea, Stefano Barlati et al.
23 citations
Among patients with treatment-resistant depression who continued esketamine nasal spray for at least six months, 76.2% responded or achieved remission. Of those who had not responded by six months, a subset improved by twelve months. Side effects occurred in 71.8% of patients at six months, decreasing to 42% at twelve months; the most common were sedation and dissociation. Only two patients stopped treatment due to tolerability issues. The findings suggest esketamine is effective and safe for mid- to long-term treatment, with a novel observation of late clinical response in some patients. Results require confirmation in larger samples and longer observation periods.
Frontiers in Psychiatry
August 31, 2020
Giovanni Martinotti, Attilio Negri, Stefania Schiavone et al.
22 citations
Recreational drug use among holidaymakers in Ibiza often involves multiple substances, both traditional and novel, leading to acute psychiatric emergencies. The pattern of poly-substance use is linked to a range of psychopathological consequences. Better understanding of the specific effects of individual drugs, clearer diagnostic signs and symptoms, and long-term follow-up studies are needed.
Current Neuropharmacology
January 14, 2021
Stefania Chiappini, Andrea Miuli, Alessio Mosca et al.
19 citations
Benzydamine, an over-the-counter anti-inflammatory drug, is being diverted and used recreationally at high dosages (500–1500 mg) for its hallucinogenic properties. A systematic review of eleven articles from 1997–2019, including case reports, surveys, and case series, along with analysis of European adverse drug reaction reports from 2005–2020, found three reported abuse cases. The findings suggest healthcare professionals should be aware of potential misuse and that emergency physicians should consider benzydamine abuse when patients present with psychotic symptoms.
Expert review of neurotherapeutics
April 1, 2025
Stefania Chiappini, Gaia Sampogna, Antonio Ventriglio et al.
17 citations
Depression involves a wide range of emotional, cognitive, and physical symptoms that disrupt daily life. Societal changes such as technological advances, economic pressures, climate change, and shifting cultural norms have altered how depression appears and is understood, leading to the identification of new depression subtypes. These include depression in adolescents and young adults, depression with social disconnection, depression with alcohol or substance use disorder, depression with gender dysphoria, and depression linked to stressful events and environmental factors. Managing these subtypes requires individualized treatment approaches. While SSRIs and SNRIs remain standard, atypical antidepressants like trazodone, ketamine, neuromodulation, and personalized psychotherapy offer hope for complex or treatment-resistant cases.
Neuroscience & Biobehavioral Reviews
October 19, 2025
Alessio Mosca, Gianluca Mancusi, Stefania Chiappini et al.
6 citations
Synthetic cannabinoids are the novel psychoactive substances most strongly associated with acute psychosis and, in some cases, persistent or relapsing psychotic disorders. Some cases show symptoms overlapping with schizophrenia, suggesting a possible risk of transition to chronic illness. Synthetic cathinones and phenethylamines are also linked to psychotic manifestations including thought disturbances and perceptual abnormalities. While many psychotic episodes are transient, a notable proportion evolve into persistent states, indicating that these substances may unmask latent vulnerabilities or directly contribute to chronic psychotic disorders. Clinicians should systematically assess NPS use in first-episode psychosis patients.
Journal of affective disorders
December 15, 2024
Giacomo d'Andrea, Andrea Miuli, Mauro Pettorruso et al.
6 citations
In patients with treatment-resistant depression, combining vortioxetine with esketamine nasal spray reduces depressive symptoms as effectively as the standard combination of an SSRI or SNRI with esketamine. The vortioxetine combination also showed a larger reduction in emotional blunting after three months and had fewer treatment-emergent side effects. These findings come from a post-hoc analysis of twenty patients, ten in each group. The authors suggest the vortioxetine-plus-esketamine regimen may be a valuable alternative, but they call for larger randomized controlled trials to confirm the results.
Psychiatry International
September 20, 2024
Alessio Mosca, Stefania Chiappini, Andrea Miuli et al.
5 citations
Piperazines, synthetic compounds with stimulant and hallucinogenic effects, are linked to acute psychotic episodes. A systematic review of 4 studies found that piperazine abuse frequently triggers symptoms such as paranoia, auditory, and visual hallucinations. The compounds' complex polyreceptor action may explain these effects, similar to other novel psychoactive substances. Recovery is common after cessation and treatment, but data on long-term outcomes are limited. Further research into piperazine abuse and specific treatment protocols for substance-induced psychosis is needed.
Transl Psychiatry
October 31, 2025
Giacomo D’andrea, Stefania Chiappini, Laura Ciavoni et al.
3 citations
Psychedelics and ketamine/esketamine show promise for treating depressive disorders by inducing rapid and sustained antidepressant effects. The review examines their biological mechanisms, including modulation of glutamate and serotonin systems, promotion of neuroplasticity, and changes in brain connectivity and network function. Neuroimaging studies reveal alterations in default mode network, fronto-limbic connectivity, and thalamic activity. Clinical changes are associated with these brain alterations, though the precise relationships remain under investigation. The work synthesizes current evidence on how these compounds produce observable brain changes and symptom improvement, highlighting the need for further research to clarify mechanisms and optimize therapeutic applications.
Current Neuropharmacology
February 20, 2025
Alessio Mosca, Stefania Chiappini, Gianluca Mancusi et al.
3 citations
Abusing certain over-the-counter medications can trigger psychotic symptoms such as paranoia, hallucinations, and thought disorders. Antihistamines, dextromethorphan, and other OTC drugs are implicated. Dextromethorphan misuse is especially linked to chronic psychosis, while other substances more often cause acute substance-induced psychosis. The review analyzed 46 relevant studies from an initial pool of 2,677 articles, highlighting the need for greater awareness and interventions to address OTC drug misuse and its psychiatric consequences.
Clinical Neuropsychopharmacology and Addiction
September 25, 2025
Stefania Chiappini, Clara Cavallotto, Andrea Miuli et al.
2 citations
About 30–50% of patients with major depression do not respond to two or more antidepressant trials, a condition called treatment-resistant depression (TRD). A narrative review of 60 studies found that glutamatergic agents such as intravenous ketamine and intranasal esketamine consistently produce rapid and clinically meaningful reductions in depressive symptoms. Augmentation with atypical antipsychotics also helps partial responders. Psychedelic-assisted therapies show sustained antidepressant benefits and affect biomarkers like BDNF and inflammatory markers. The findings suggest a shift toward personalized, mechanism-driven treatments for TRD, with ketamine and esketamine offering rapid relief for acute high-risk cases and psychedelics remaining experimental but promising as adjunctive options.
Psychiatry Research
August 18, 2025
Ilenia Rosa, L. Padula, Francesco Semeraro et al.
2 citations
Treatment-resistant depression (TRD) challenges standard approaches, prompting a shift toward non-monoaminergic interventions like neuromodulation and glutamatergic agents. This narrative review examines the endocannabinoid system (ECS) as a potential common pathway for these treatments. Evidence indicates that repetitive transcranial magnetic stimulation (rTMS) and electroconvulsive therapy (ECT) increase endocannabinoids anandamide and 2-arachidonoylglycerol, correlating with clinical improvement. Ketamine and esketamine modulate CB1 receptors, while psilocybin restores 2-AG and enhances CB1 expression in mood-related brain regions. These findings suggest ECS modulation may unify diverse antidepressant mechanisms in TRD, offering a promising target for novel therapies.
Journal of Psychiatric Research
June 19, 2025
Valerio Ricci, Ilenia di Muzio, Mancusi Gianluca et al.
2 citations
Synthetic cannabinoid users experiencing first-episode psychosis show more severe positive psychotic symptoms, persistent aberrant salience, and limited recovery of alexithymia over six months compared to natural cannabis users and non-users. Dissociative symptoms are more prominent in both user groups, with synthetic cannabinoid users showing minimal improvement. Negative symptoms are higher in non-users but decrease across all groups. Alexithymia correlates with specific aberrant salience subscales, particularly Feelings of Increased Significance and Sense Sharpening. These findings indicate synthetic cannabinoids are associated with more severe and persistent psychotic symptoms and emotional dysregulation than natural cannabis.
Scientific reports
March 27, 2026
Gianmauro Palombelli, Valentina Zecca, Marta Boffa et al.
1 citation
In a rat model of treatment-resistant depression (Wistar-Kyoto rats exposed to chronic mild stress), brain scans revealed metabolic and structural changes distinct from non-depressed controls. Magnetic resonance spectroscopy showed reduced glutamate, glutamine, and taurine in the prefrontal cortex and decreased glutamine and choline compounds in the hippocampus, along with increased myo-inositol in the prefrontal cortex. Diffusion tensor imaging indicated higher mean diffusivity in both regions, consistent with demyelination or axonal loss, and lower fractional anisotropy in the hippocampus, suggesting compromised white-matter integrity. These findings mirror depression- and stress-related brain changes in humans, supporting the model's use for testing novel treatments like rTMS and psychedelics.
Brain Sci
September 17, 2025
Alessio Mosca, Stefania Chiappini, Andrea Miuli et al.
1 citation
Synthetic cannabinoids can cause psychosis that is often severe and difficult to treat. This systematic review examined published case reports and case series to identify effective treatment strategies. The review found that benzodiazepines and antipsychotics are commonly used, but many patients require intensive care and prolonged hospitalization. No single treatment protocol emerged as clearly superior, and outcomes varied widely, with some patients recovering fully while others experienced persistent psychotic symptoms. The authors suggest that early recognition and aggressive management may improve outcomes, but more research is needed to establish standardized treatment guidelines.
The International Journal of Neuropsychopharmacology
February 1, 2025
Clara Cavallotto, Giacomo D’andrea, Andrea Miuli et al.
1 citation
In patients with treatment-resistant depression, combining the antidepressant vortioxetine with esketamine nasal spray was as effective as the standard combination of an SSRI or SNRI with esketamine in reducing depressive symptoms over three months. The vortioxetine combination showed a larger effect in reducing emotional blunting and was linked to fewer treatment-emergent side effects, including dissociative symptoms. These findings suggest vortioxetine plus esketamine may be a valuable alternative, though larger randomized trials are needed to confirm the results.
Psychiatry Research Case Reports
October 18, 2023
Giacomo D’andrea, Ornella di Marco, Francesco Maria Semeraro et al.
1 citation
A 56-year-old man with rapid cycling bipolar disorder, experiencing four or more mood episodes per year, received esketamine nasal spray during a depressive episode and was followed for 18 months. He showed substantial mood stabilization, with only a brief depressive episode when treatment was stopped for three months, which resolved after restarting esketamine. Mild dissociative symptoms occurred with initial doses, but no other serious side effects were reported. This case suggests esketamine nasal spray may have mood-stabilizing effects for rapid cycling bipolar disorder, a condition that often responds poorly to lithium and standard treatments.