Autism, Sleep, and Medicinal Cannabis: 18-Month Prospective Registry Outcomes on Efficacy and Safety

Purpose Sleep disturbances are highly prevalent in children with autism and are associated with worsening daytime functioning and reduced family quality of life. Despite widespread real-world use of medicinal cannabis to address sleep difficulties, long-term prospective data on efficacy and safety in pediatric autism populations remain limited. This study evaluated 18-month efficacy and safety outcomes of medicinal cannabis use on sleep in children with autism using a prospective clinic registry. Methods This prospective observational study enrolled 68 children with autism initiating medicinal cannabis treatment within a specialty clinic registry. Cannabis products included tinctures and gummies. Caregiver-reported sleep duration was assessed before treatment initiation and after sustained exposure. Caregiver Global Impression of Change (CGIC) was recorded using a 7-point ordinal scale ranging from substantially improved to substantially worsened. Of the initial cohort of 68, 57 participants completed 18 months of follow-up: 11 discontinued treatment due to side effects (n = 7), cost (n = 2), or travel barriers (n = 2). Descriptive and paired analyses were conducted to evaluate sleep outcomes and caregiver-reported change. Results Among participants completing at least 18 months of follow-up, mean caregiver-reported sleep duration increased from 6.8 to 8.1 hours, corresponding to a mean increase of 1.3 hours (95% CI 0.8–1.7). Improvements were most pronounced among children with more severe baseline sleep deprivation, with those sleeping less than six hours per night demonstrating a mean increase of 2.2 hours. Across caregiver-reported sleep domains, approximately 70-75% of caregivers reported improvement in sleep onset, sleep maintenance, and overall sleep quality, with minimal reports of worsening. CGIC ratings also indicated improvement in both child and caregiver quality of life in the majority of participants. Caregivers additionally reported modest, variable improvements across several behavioral domains, including attention, sensory sensitivities, anxiety, and repetitive behaviors, which were assessed descriptively. Adverse effects were most commonly reported early in treatment and declined over time, with treatment discontinuation due to persistent adverse effects occurring in a minority of participants and no serious adverse events observed.