Background: The Canary Islands longitudinal study on non-pharmacological treatments showed the overall effectiveness of mindfulness in Alzheimer’s disease (AD). However, no specific data on the maintenance of cognitive capacities were presented. Objective: To determine whether the practice of mindfulness modifies the course of cognitive impairment in AD. Methods: Design: Longitudinal, non-inferiority and equivalence, randomized clinical trial, repeated-measures design, with three experimental groups and one control group. Participants: Patients with AD who voluntarily attended the Lidia García Foundation (n = 502). Only those who were treated with donepezil and MMSE ≥18 were included (n = 120). Intervention: Over a two-year period, each group carried out three weekly sessions of stimulation based on mindfulness, cognitive stimulation therapy, and progressive muscle relaxation. Measures: Cognitive assessment CAMDEX-R (MMSE and CAMCOG). Statistical analysis: Repeated-measures ANOVA (p < 0.05) and the effect size Cohen’s d were performed. Results: The mindfulness group showed significant scores compared with the control and muscle relaxation groups (p < 0.05), while mindfulness and cognitive stimulation therapy were equivalent (p≥0.05). Group cognitive stimulation evolved better than the control (p < 0.05) group but not better than the muscle relaxation group (p≥0.05). The effect size compared over two years was large for the mindfulness group (p≥0.80), moderate for the relaxation group (p≥0.50), and low for the cognitive stimulation group (p≥0.20). Conclusion: The practice of mindfulness maintained cognitive function over a period of two years. This longitudinal study suggests that mindfulness can be used as a non-pharmacological treatment to slow cognitive impairment in AD.

In psychedelic therapy, the importance of set and setting is a fundamental but under-researched assumption. The aim of this study is to correlate variables of set (psychedelic use motivation) and setting (psychedelic use location and type of companion) with psychopathology, wellbeing and personality variables. A sample of 1022 participants of the Spanish-speaking population was collected through an online survey. A novel instrument, the Psychedelic Use Scale (PUS), was developed to measure substance use variables of LSD, mescaline, psilocybin, DMT, 5-Meo-DMT, ketamine, Salvia divinorum, ibogaine and MDMA. Various personality, well-being and psychopathology instruments were implemented to measure outcome variables. Growth motivations, natural settings and presence of significant others predicted less psychopathology, greater wellbeing and meaningfulness of psychedelic experiences, whereas problematic motivations predicted greater psychopathology, lower wellbeing and did not predict meaningfulness of psychedelic experiences. Based on these results, we suggest experimental hypotheses for future clinical trials and longitudinal studies with potential clinical implications.

Psychedelics are experiencing a strong renaissance and will soon be incorporated into clinical practice. However, there is uncertainty about how much harm they can cause at what doses. This review aimed to collect information on the health-hazardous doses of psychedelic substances, to be aware of the risks to which patients may be subjected. We focused on ergolamines, simple tryptamines, and phenylethylamines. We reviewed articles published in major medical and scientific databases. Studies reporting toxic or lethal doses in humans and animals were included. We followed PRISMA criteria for revisions. We identified 3032 manuscripts for inclusion. Of these, 33 were ultimately useful and gave relevant information about effects associated with high psychedelics doses. Despite having different molecular structures and different mechanisms of action, psychedelics are effective at very low doses, are not addictive, and are harmful at extremely high doses. For LSD and psilocybin, no dose has been established above which the lives of users are endangered. In contrast, MDMA appears to be the most dangerous substance, although reports are biased by recreational missuses. It seems that it is not only the dose that makes the poison. In the case of psychedelics, the set and setting make the poison.

This study investigated the effects of low-dose 1cp-LSD, a prodrug of LSD, on canine anxiety, while exploring the influence of owner psychopathology on treatment outcomes. Seven dogs exhibiting anxiety-related behaviors were recruited and received 2.5, 5, or 10 µg of 1cp-LSD orally every three days for 30 days. One additional dog, which did not meet clinical criteria for anxiety but whose owner perceived it as anxious, received a placebo (saccharin) as an observational case. Anxiety levels were assessed using validated scales at baseline, post-treatment, and one month after treatment cessation. Owners’ neuroticism and psychopathological dimensions were evaluated using the IPIP and SA-45 scales. Linear regression analyses examined associations between anxiety reduction, administered dose, and owner psychological traits. A significant reduction in separation anxiety scores was observed post-treatment (mean: 11.3 ± 3.0, p = 0.023). Higher 1cp-LSD doses correlated with greater anxiety reduction (B = −1.15, 95% CI = [−2.29, −0.003], p = 0.050). Additionally, higher owner psychoticism scores were associated with smaller improvements in canine anxiety (p = 0.035). Anxiety levels remained low one month after treatment, with significant associations between canine anxiety and the owners’ hostility, interpersonal sensitivity, and paranoid ideation. These findings support the potential role of low-dose serotonergic psychedelics in managing canine anxiety and suggest an association between caregiver psychological traits and treatment outcomes. The sustained reduction in anxiety behaviors also suggests a meaningful and lasting improvement in animal welfare. However, significant results should be interpreted cautiously due to the small sample size. Further blinded, controlled studies are needed to validate these preliminary observations and assess broader applications in veterinary behavioral medicine.