Abstract
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.