Search Results (508)

Background/Objectives: Muscle dysmorphia (MD), a subtype of body dysmorphic disorder, is prevalent among males who engage in the non-medical use of anabolic–androgenic steroids (AASs) and performance-enhancing drugs (PEDs). These individuals often experience severe psychopathology, including mood instability, compulsivity, and a distorted body image. Despite its clinical severity, no randomized controlled trials (RCTs) have evaluated structured psychological treatments in this subgroup. This study aimed to assess the efficacy of a manualized cognitive behavioral therapy (CBT) protocol in reducing MD symptoms and associated psychological distress among male steroid users. Results: Participants in the CBT group showed significant reductions in MD symptoms from the baseline to post-treatment (MDDI: p < 0.001, d = 1.12), with gains sustained at follow-up. Large effect sizes were also observed in secondary outcomes including depressive symptoms (PHQ-9: d = 0.98), psychological distress (K10: d = 0.93), disordered eating (EDE-Q: d = 0.74), and exercise addiction (EAI: d = 1.07). No significant changes were observed in the control group. Significant group × time interactions were found for all outcomes (all p < 0.01), indicating CBT’s specific efficacy. Discussion: This study provides the first RCT evidence that CBT significantly reduces both core MD symptoms and steroid-related psychopathology in men engaged in AAS/PED misuse. Improvements extended to mood, body image perception, and compulsive exercise behaviors. These findings support CBT’s transdiagnostic applicability in addressing both the cognitive–behavioral and affective dimensions of MD. Materials and Methods: In this parallel-group, open-label RCT, 59 male gym-goers with DSM-5-TR diagnoses of MD and a history of AAS/PED use were randomized to either a 12-week CBT intervention (n = 30) or a waitlist control group (n = 29). CBT sessions were delivered weekly online and targeted distorted muscularity beliefs, compulsive behaviors, and emotional dysregulation. Primary and secondary outcomes—Muscle Dysmorphic Disorder Inventory (MDDI), PHQ-9, K10, EDE-Q, EAI, and BIG—were assessed at the baseline, post-treatment, and 3-month follow-up. A repeated-measures ANOVA and paired t-tests were used to analyze time × group interactions. Conclusions: CBT offers an effective, scalable intervention for individuals with muscle dysmorphia complicated by anabolic steroid use. It promotes broad psychological improvement and may serve as a first-line treatment option in high-risk male fitness populations. Future studies should examine long-term outcomes and investigate implementation in diverse clinical and cultural contexts. Full article

Background/Objectives: Neurofibromatosis type 1 (NF1) and Noonan syndrome spectrum disorders (NSSD) are the most common RASopathies, resulting from germline mutations that affect the RAS-MAPK signaling pathway. Both are associated with increased risk for neurodevelopmental and psychiatric conditions, yet few studies have used structured diagnostic interviews to compare their psychiatric comorbidities. Methods: We conducted clinician-administered DSM-5 diagnostic assessments (KSADS) in 123 children with RASopathies (NF1 = 29, NSSD = 94; ages 5–15). Diagnosis prevalence was compared within each group and to population-based estimates. Results: Psychiatric diagnoses were highly prevalent, at 79.3% in NF1 and 76.6% in NSSD, with ADHD (NF1 = 72.4%, NSSD = 51.1%) and anxiety disorders (NF1 = 37.9% and NSSD = 43.6%) being the most common, rates substantially higher than those reported in general population estimates. Behavioral and sleep disorders were identified in approximately 25% of both groups. Notably, social anxiety disorder was identified in 14.9% of NSSD but not in NF1. Full-scale IQ did not significantly differ by diagnosis status. Specific anxiety disorders, elimination disorders, obsessive–compulsive disorder, and post-traumatic stress disorder were characterized, expanding the known psychiatric phenotype of RASopathies. Conclusions: Children with NF1 and NSSD demonstrate similarly high rates of ADHD, anxiety, and behavioral disorders compared to the general population; in addition, we report sleep disorders in NSSD and characterize psychiatric disorders not previously described in RASopathies. The shared psychiatric profiles may reflect the common effect of RAS-MAPK pathway dysregulation on psychiatric outcomes. These findings highlight the need for early, syndrome-informed mental health screening and intervention in the clinical care of individuals with RASopathies. Full article

Background and Objectives: Polycystic ovary syndrome (PCOS) is associated with an elevated risk of impaired mental health and psychiatric disorders, such as depression and anxiety. Physical factors like weight and hirsutism, as well as psychological factors, such as self-esteem and coping strategies, are all known to have an influence on mental health status. Aim: To assess psychological symptoms in women with and without PCOS, by use of the well-established, validated self-report questionnaire: Symptom Checklist-90-Revised (SCL-90); to determine the reliability of the SCL-90 for assessment of PCOS patients. Design: Prospective case-control study. Methods: Psychological symptoms were assessed using the German version of the SCL-90 in 31 PCOS women and 31 healthy controls. To test the impact of various parameters on numerical outcome parameters, correlation analyses were conducted. Results: PCOS women revealed significantly increased SCL-90 scores in seven out of the nine subscales (hostility subscale, anxiety subscale, depression subscale, paranoid ideation subscale, psychoticism subscale, somatization subscale, interpersonal sensitivity subscale, obsessive compulsive subscale), as well as in all three global indices (p < 0.05). SCL-90 scores were significantly positively correlated with perceived total stress and perceived helplessness and significantly negatively correlated with perceived self-efficacy (p < 0.05). Conclusions: PCOS women experienced higher levels of psychological symptoms including depressive and anxiety symptoms. Higher perceived stress, higher perceived helplessness and lower self-efficacy were associated with more psychological symptoms. Hence, there is a need to support PCOS women with their emotional regulation and coping strategies. Full article

Background: Research on sex differences in personality disorders profiles among individuals with Alcohol Use Disorder (AUD) remains limited. This study aimed to examine sex differences in personality disorders in AUD individuals attending to an outpatient alcohol and drugs treatment unit. Methods: Persons seeking alcohol detoxification treatment were assessed with the Millon Clinical Multiaxial Inventory-III (MCMI-III) after abstinence. Both dimensional trait scores and cluster personality disorders types distribution were analyzed. A total of 216 subjects, 114 women (53%) and 102 men (47%), participated in the study. Results: No sex differences were found for paranoid, schizoid or schizotypal traits scores of Cluster A types. Women exhibited higher scores on the Cluster B histrionic trait (48 ± 22 vs. 39 ± 23, p = 0.012), with no differences in antisocial, borderline, or narcissistic trait scores. Narcissistic personality disorder was more prevalent in men than women (44% vs. 20%, p = 0.012). Cluster C dependent (52 ± 24 vs. 46 ± 20, p = 0.025) and obsessive-compulsive (54 ± 20 vs. 43 ± 19, p = 0.012) traits scores were elevated in women, but only dependent personality disorder prevalence differed categorically (38% women vs. 15% men, p = 0.012). Conclusions: Employing both dimensional and cluster approaches enriches personality disorder research in AUD. Dependent personality disorder in Cluster C robustly differentiates sexes, while personality disorder patterns in Clusters A and B show minimal sex differences when both approaches are considered. Full article

Aims. In the present study, we investigated the associations between the three identity dimensions of Kaufman (Consolidated Identity, Disturbed Identity, Lack of Identity) and symptoms of personality disorders (PDs) in 176 female inpatients with an eating disorder (ED). We examined five aspects: the prevalence of categorical PD diagnoses in patients with EDs; the relationship between dimensional PD scores and identity dimensions as well as their relationships with age and ED subtype; and the unique variance in dimensional PD scores explained by identity dimensions, while controlling for age and ED subtype. Methods. To assess identity functioning, we made use of the Self-Concept and Identity Measure, and to assess PDs, we used the categorical and dimensional scores of the Assessment of DSM-IV Personality Disorders. Results. The findings showed that the avoidant, obsessive–compulsive, and borderline categorical PDs were the most frequently reported PDs. Age was negatively related to all Cluster B PDs and Disturbed Identity, and binge-eating/purging ED patients reported significantly more Cluster B PD features compared to restrictive ED patients. ED subtype and identity dimensions were unrelated. Correlational analysis showed that all dimensional PD scores were positively related to Disturbed Identity and Lack of Identity and negatively related to Consolidated Identity. The results of the hierarchical regression analyses showed that Cluster A PDs were significantly predicted by Lack of Identity, controlled for age and ED subtype. Additionally, Cluster B PDs were significantly predicted by Disturbed Identity. Finally, two of the three cluster C PDs were predicted by Lack of Identity (avoidant and obsessive–compulsive PD), whereas the dependent PD was explained by Disturbed Identity. Conclusions. The co-occurrence of identity issues in both PDs and EDs underscores the role of identity as a transdiagnostic feature. Accordingly, using identity-based interventions in treatment may have broad therapeutic benefits across these disorders. Full article

Over the past three turbulent decades, research has profoundly reshaped our understanding of chronic Toxoplasma gondii infection—traditionally regarded as harmless in immunocompetent individuals—unveiling its surprising impact on human health, performance, and behavior. This review emphasizes the effects of chronic Toxoplasma infection on physical and mental health, cognitive performance, and behavioral changes, highlighting key findings from studies investigating these domains, with a particular focus on both ultimate and proximate mechanisms underlying the observed effects. To this end, the primary focus will be on human studies; however, animal model studies will also be thoroughly considered when necessary and appropriate, to provide context and additional important information. Research demonstrates that chronic Toxoplasma infection may contribute to a broad spectrum of physical health issues. Ecological studies have revealed correlations between toxoplasmosis prevalence and increased morbidity and mortality from various conditions, including cardiovascular diseases, neurological disorders, and certain cancers. Large-scale cross-sectional studies have further shown that infected individuals report a higher incidence of numerous health complaints and diagnosed diseases, suggesting a significant impact on overall physical well-being. In addition to physical health, lifelong Toxoplasma infection (subclinical toxoplasmosis) has been implicated in cognitive impairments and behavioral changes. Studies have reported associations between infection and poorer performance in areas such as reaction time, processing speed, working memory, and executive function. Many of these behavioral changes likely relate to worsened health and a shift towards a “fast life history strategy.” These cognitive deficits can have significant implications for daily functioning and performance. Furthermore, the role of Toxoplasma infection in the development or exacerbation of mental health disorders has been extensively investigated. Meta-analyses, ecological studies, and large-scale observational studies have demonstrated associations between Toxoplasma infection and an increased risk of disorders such as schizophrenia and obsessive–compulsive disorder. While the precise mechanisms underlying these associations remain under investigation, research suggests that neuroinflammation and alterations in neurotransmitter systems are likely to play a role. Far from being harmless, subclinical toxoplasmosis is increasingly recognized as a hidden factor influencing human health, behavior, and cognitive performance—with implications that extend well beyond the individual to public health at large. Further research is warranted to elucidate the complex interplay between Toxoplasma infection, host physiology, and the development of various physical, cognitive, behavioral, and mental health conditions. Full article

Background. Cognitive-behavioral theories suggest that obsessions in obsessive-compulsive disorder (OCD) develop from maladaptive misinterpretations and coping strategies of unwanted intrusive thoughts (UITs). Models of Body Dysmorphic Disorder (BDD) and Illness Anxiety Disorder (IAD) propose that these symptoms stem from similar misinterpretations of common UITs relating to perceived defects in appearance and illness. This study examines whether maladaptive misinterpretations and control strategies leading to the escalation of obsessional UITs to OCD symptoms also have a similar effect on the development of BDD and IAD. More specifically, we examined whether misinterpretations and neutralizing responses mediate the associations between the frequency of disorder-specific UITs and symptoms of these disorders. Method. A total of 625 non-clinical participants from four countries completed the Questionnaire of Unpleasant Intrusive Thoughts (QUIT) that assesses OCD, BDD and IAD-related UITs and their associated misinterpretations and neutralizing strategies, as well as self-report measures of OCD, BDD, and IAD symptoms. Parallel multiple mediation models were conducted. Results. The frequency of OCD, BDD and IAD-related UITs predicted symptoms of each disorder. Dysfunctional appraisals and neutralizing behaviors mediated the associations between disorder-specific UITs and symptoms in OCD and IAD. The IAD model accounted for a smaller proportion of variance than the OCD model. No mediating effects were found for BDD symptoms. Conclusions. Experiencing disturbing UITs is a transdiagnostic risk factor of OCD, BDD and IAD, and is associated with symptoms of these disorders. Maladaptive interpretation of UITs and neutralizing strategies should be specific targets in the assessment and treatment of OCD and IAD. The absence of mediation effects for BDD could be due to the limitations observed on the self-report used to assess BDD symptoms and/or the low relevance of the misinterpretations and control strategies assessed by the QUIT, which are more typically endorsed by individuals with OCD. Full article

Background: Food addiction (FA) is an emerging construct that mirrors the behavioral and neurobiological characteristics of substance use disorders. Despite growing interest, its association with specific psychiatric disorders among bariatric patients remains understudied. Objective: Our aim was to examine the prevalence and strength of associations between FA and seven major psychiatric disorders in individuals who underwent bariatric surgery. Methods: In a sample of 100 post-bariatric patients referred for psychiatric evaluation, FA was assessed using the modified Yale Food Addiction Scale 2.0 (mYFAS 2.0), and psychiatric disorders were diagnosed using the Mini International Neuropsychiatric Interview (MINI). Logistic regression models were used to estimate adjusted odds ratios (aORs) for the association between FA and each psychiatric disorder, controlling for sex, age, body mass index (BMI), employment status, the number of children, clinical comorbidities, physical activity, family psychiatric history, and region of residence. Results: FA was present in 51% of the sample. Descriptive analyses revealed a significantly higher prevalence of major depressive disorder, panic disorder, generalized anxiety disorder, social anxiety disorder, agoraphobia, obsessive–compulsive disorder, and bulimia nervosa among individuals with FA. Multivariate models showed robust associations between FA and bulimia nervosa (aOR = 19.42, p < 0.05), generalized anxiety disorder (aOR = 2.88, p < 0.05), obsessive–compulsive disorder (aOR = 6.64, p < 0.05), agoraphobia (aOR = 3.14, p < 0.05), social anxiety disorder (aOR = 4.28, p < 0.05) and major depressive disorder (aOR = 2.79, p < 0.05). Conclusions: FA is strongly associated with a range of psychiatric comorbidities in post-bariatric patients, reinforcing the need for comprehensive mental health screening in this population. These findings underscore the potential role of FA as a clinical marker for stratified risk assessment, supporting more personalized approaches to mental health monitoring and intervention following bariatric surgery. Full article

Introduction: Substance use disorders (SUDs) pose a significant public health challenge, with current treatments often exhibiting limited effectiveness and high relapse rates. Transcranial direct current stimulation (tDCS), a noninvasive neuromodulation technique that delivers low-intensity direct current via scalp electrodes, has shown promise in various psychiatric and neurological conditions. In SUDs, tDCS may help to modulate key neurocircuits involved in craving, executive control, and reward processing, potentially mitigating compulsive drug use. However, the precise neurobiological mechanisms by which tDCS exerts its therapeutic effects in SUDs remain only partly understood. This review addresses that gap by synthesizing evidence from clinical studies that used neuroimaging (fMRI, fNIRS, EEG) and blood-based biomarkers to elucidate tDCS’s mechanisms in treating SUDs. Methods: A targeted literature search identified articles published between 2008 and 2024 investigating tDCS interventions in alcohol, nicotine, opioid, and stimulant use disorders, focusing specifically on physiological and neurobiological assessments rather than purely behavioral outcomes. Studies were included if they employed either neuroimaging (fMRI, fNIRS, EEG) or blood tests (neurotrophic and neuroinflammatory markers) to investigate changes induced by single- or multi-session tDCS. Two reviewers screened titles/abstracts, conducted full-text assessments, and extracted key data on participant characteristics, tDCS protocols, neurobiological measures, and clinical outcomes. Results: Twenty-seven studies met the inclusion criteria. Across fMRI studies, tDCS—especially targeting the dorsolateral prefrontal cortex—consistently modulated large-scale network activity and connectivity in the default mode, salience, and executive control networks. Many of these changes correlated with subjective craving, attentional bias, or extended time to relapse. EEG-based investigations found that tDCS can alter event-related potentials (e.g., P3, N2, LPP) linked to inhibitory control and salience processing, often preceding or accompanying changes in craving. One fNIRS study revealed enhanced connectivity in prefrontal regions under active tDCS. At the same time, two blood-based investigations reported the partial normalization of neurotrophic (BDNF) and proinflammatory markers (TNF-α, IL-6) in participants receiving tDCS. Multi-session protocols were more apt to drive clinically meaningful neuroplastic changes than single-session interventions. Conclusions: Although significant questions remain regarding optimal stimulation parameters, sample heterogeneity, and the translation of acute neural shifts into lasting behavioral benefits, this research confirms that tDCS can induce detectable neurobiological effects in SUD populations. By reshaping activity across prefrontal and reward-related circuits, modulating electrophysiological indices, and altering relevant biomarkers, tDCS holds promise as a viable, mechanism-based adjunctive therapy for SUDs. Rigorous, large-scale studies with longer follow-up durations and attention to individual differences will be essential to establish how best to harness these neuromodulatory effects for durable clinical outcomes. Full article

Background and Objectives: During exam sessions, many students experience high levels of stress caused by the large volume of material to study, tight deadlines, and pressure to achieve top grades. This study aimed to examine the relationship between academic stress, sleep disturbances, and eating behaviors by using validated questionnaires administered to a student sample. As stress levels increased, the data revealed a higher frequency of insomnia symptoms and disordered eating, including behaviors such as compulsive eating and irregular meal patterns. Materials and Methods: This cross-sectional, correlational study was conducted on a convenience sample of 317 university students from various academic centers across Romania. Participants were recruited via online distribution of a self-administered questionnaire during a four-month period, including exam sessions. The survey included the Perceived Stress Scale (PSS), the Insomnia Severity Index (ISI), and the Eating Disorder Examination Questionnaire (EDE-Q), alongside additional items assessing perceived links between stress, sleep, and eating behaviors, and the use of medication. Data were analyzed using SPSS with Spearman correlations, t-tests, and linear regression. Results: Statistical analyses revealed significant and positive associations between perceived stress levels and insomnia, as indicated by Spearman’s correlation (p < 0.01). A similar significant correlation was identified between perceived stress and disordered eating behaviors among students. Specifically, the feeling of being overwhelmed by academic workload showed a strong positive correlation with a lack of control over eating behaviors (r = 0.568). Furthermore, linear regression analysis confirmed a significant predictive relationship between feeling overwhelmed and the tendency to eat excessively beyond initial intentions, with a standardized regression coefficient B = 0.581 (p < 0.001). A separate regression analysis focusing on exam-related stress and episodes of compulsive eating behavior demonstrated a comparable result (B = 0.573, p < 0.001), indicating a robust positive association. Additionally, independent samples t-tests demonstrated that students experiencing high levels of stress during the exam period reported significantly greater difficulties with sleep initiation and higher levels of disordered eating compared to their peers with lower stress levels. The difference in insomnia scores was highly significant (t = 11.516, p < 0.001), as was the difference in eating behavior scores (t = 10.931, p < 0.001). Conclusions: These findings underscore the need for emotional support services and effective stress management strategies, enabling students to navigate academic demands without compromising their mental or physical well-being. Full article

Background/Objectives: Duchenne muscular dystrophy (DMD) is often discussed in the literature with regard to physical impairments. This narrative review aims to show that living with DMD involves psychological, psychosocial, and cognitive aspects in addition to the well-known physical complications. Methods: Firstly, this review examines the main cognitive functions affecting subjects with DMD and the possible role of dystrophin gene mutations on the central nervous system. Secondly, it analyzes the comorbidity between DMD, neurodevelopmental disorders (autism spectrum disorders, attention-deficit/hyperactivity disorder, obsessive–compulsive disorder) and psychopathological traits (anxiety and/or depressive symptoms). Finally, the review addresses the relatively sparse literature investigating the positive aspects associated with the experience of DMD, like psychosocial resources, resilience, subjective well-being, positive individual and social functioning, and social support. Results: DMD has a significant impact on cognitive areas, probably due to dystrophin deficiency in the brain. The prevalence of neurodevelopmental comorbidities and psychopathological symptoms is also higher in people with DMD than in the general population. Despite these challenges, emerging studies highlight the role of psychosocial and environmental resources, including resilience and supportive social relations, in promoting a good quality of life and successful adaptation to disease progression. Conclusions: Early recognition of the above difficulties and strengths could ensure better care and promote an overall better quality of life for people with DMD and their families, physically, psychologically, and socially. Preclinical and clinical research is moving in the direction of finding new therapies, treatments, and psychosocial interventions to pursue these goals. Full article

Background/Objectives: The prevalence of orthorexia nervosa (ON) is increasing over time. Additionally, specific social categories seem to be more affected. In the literature, the prevalence of university students suffering from ON is unclear, ranging from 7% to 83%. Nonetheless, ON shares pathological traits with both eating and obsessive–compulsive disorders, making its etiology and therapeutic perspectives complex. This study aimed to investigate the prevalence of ON and explore its psychological characteristics in a sample of university students. Methods: A total of 205 students from the University of Parma were consecutively recruited using a convenience sampling procedure. Participants completed the Orthorexia Nervosa Questionnaire-15 (ORTO-15) to assess ON, the Eating Disorder Inventory-3 (EDI-3) to investigate eating behavior, the Symptom Checklist-90-Revised (SCL-90-R) to detect psychological symptoms, and the P Stress Questionnaire (PSQ) to describe stress-related lifestyle. Based on the scores obtained on the ORTO-15, a group of orthorexic students (ORTO-15 score ≤ 35) was compared with a group of non-orthorexic students (ORTO-15 score > 35). Results: The prevalence of university students with ON was nearly 42% (specifically, 41.95%). Furthermore, orthorexic students reported significantly higher levels of emotional dysregulation, perfectionism, and asceticism on the EDI-3 as well as affective problems and overcontrol in general. Furthermore, although there were no differences between the groups regarding psychological symptoms, an increase in sense of responsibility, vigor, and hyperactivity, as well as decreased free time on the PSQ, characterized the orthorexic student group. Conclusions: The results support that orthorexia nervosa emerged as a concerning phenomenon among university students, with increasing evidence pointing to its psychological correlates. Nonetheless, the fact that ON shares psychological characteristics with eating disorders highlights the clinical importance of implementing multidimensional assessments and multidisciplinary therapeutic approaches for individuals presenting with orthorexic-type eating behavior disorders. Full article

Psychiatric neurosurgery is undergoing a profound transformation, propelled by advances in neurotechnology, connectomics, and personalized medicine. Once controversial, surgical interventions are now guided by detailed functional brain mapping and precise neuromodulation techniques, such as deep brain stimulation (DBS), which offer therapeutic options for patients with severe, treatment-resistant psychiatric disorders. This manuscript reviews the current techniques, including lesion-based procedures and DBS, and explores their mechanisms of action, from synaptic plasticity to large-scale network modulation. It highlights recent progress in neuroimaging, connectomic targeting, and artificial intelligence applications for surgical planning and the prediction of treatment responses. Ethical considerations—including informed consent, identity, and long-term follow-up—are critically examined in light of these advances. Furthermore, the growing role of minimally invasive procedures and wearable integrated neurotechnologies is discussed as part of a shift toward dynamic and adaptive interventions. Although still investigational, psychiatric neurosurgery is emerging as a technologically sophisticated field that demands rigorous clinical evaluation, ethical accountability, and an individualized approach to restoring function and autonomy in some of the most disabling mental illnesses. Full article

Tourette syndrome (TS) is the most common cause of tics. Tics are classified as motor and phonic tics. The latter (previously also referred to as “vocal tics”) are manifested by simple sounds (simple phonic tics) or complex, often semantically meaningful utterances (complex phonic tics). Methods: We compared the clinical and demographic features of consecutive patients with TS who exhibited simple and complex phonic tics. Results: There were 149 patients, 117 (78.5%) of whom were males; the mean age at evaluation was 19.61 ± 12.97 years. In total, 35 (23.5%) of these manifested complex phonic tics, and 26 (17.4%) had verbalizations. No statistically significant differences were observed between TS patients with simple versus complex phonic tics with respect to sex, age at onset, age at presentation, or comorbid attention-deficit/hyperactivity disorder or obsessive–compulsive disorder. Patients with complex phonic tics more frequently had trunk tics (p = 0.002), complex motor tics (p < 0.001), copropraxia (p = 0.002), a wider variety of phonic tics (p < 0.001) and greater tic severity (p = 0.001). The multivariate regression analysis showed an independent association between trunk tics and complex phonic tics. Conclusions: Complex phonic tics seem to be part of a more widely distributed, severe, and complex presentation of TS, likely representing a continuum within the spectrum of motor and phonic tics. Full article

Obsessive–compulsive disorder (OCD) has an estimated prevalence between 1 and 2.3%. Existing treatments may not be suitable or effective for all people with OCD, and there is increasing interest in whether these individuals may benefit from the use of cannabis-based medical products (CBMPs). We document the characteristics of 257 people reporting a diagnosis of OCD within Project T21, a study of medical cannabis patients, and examined whether the use of prescribed cannabinoids improves quality of life. Individuals with OCD were prescribed an average of 2.2 CBMPs, with most products classified as THC-dominant flowers (73.7%). Three months after initiating treatment, there were substantial improvements in quality of life (Cohen’s d = 0.48; 95% CI = 0.29–0.65), general health (Cohen’s d = 0.43; 95% CI = 0.26–0.61), mood/depression (Cohen’s d = 0.85; 95% CI = 0.65–1.04), and sleep (Cohen’s d = 0.61; 95% CI = 0.43–0.79). There was a corresponding reduction in anxiety symptoms among the subsample who completed the GAD-7 (Cohen’s d = 1.14; 95% CI = 0.84–1.44). Eight individuals (5.7%) reported a total of 14 adverse effects, with the majority of these (57%) being described as mild. Given emerging evidence that those with OCD can benefit from CBMPs, coupled with the increased availability of these unlicensed products internationally, there is a need for more research, including clinical trials, to identify those who may benefit most from the use of these medicines. Full article