Introduction
Neuropsychiatric symptoms (NPS) may be disruptive and problematic for patients with Alzheimer’s disease (AD) and for their caregivers. Cannabidiol (CBD) may be a safer alternative. The objective was to evaluate whether CBD-rich oil was effective, and safe in adults with NPS secondary to AD.

Methods
An open-label, prospective cohort, single-center study in patients with AD onset after the age of 65 with untreated NPS. A CBD-rich oil was administrated 0.1 mL sublingually every 8–12 h, up-titrated weekly. The primary outcome was to establish a reduction in the NPI-Q severity score of >30% at 12 weeks compared with the baseline. A p value of <0.05 was statistically significant.

Results
Between July 2020 and July 2023, 59 (93.5%) patients completed ≥3 months of follow-up. The patients were under treatment for a mean of 23.2 months, the median dose of CBD was 111 mg/day. The median NPI-Q severity and caregiver’s distress scores at baseline were 24 and 29, respectively. At 3 months, the median NPI-Q severity score shifted to 12 (p < 0.001) and 14 (p < 0.001), respectively. The proportion of patients who achieved a reduction in the NPI-Q severity score of >30% was 94.9%, while a reduction of >50% was achieved by 54.2%. The improvement was maintained for up to 24 months.

Conclusion
This study shows that CBD-rich oil is an effective and safe therapy for treating NPS in AD patients, while also reducing the caregivers’ distress.