Full-Spectrum Cannabidiol Oil for Anxiety and Depressive Symptoms in Parkinson's Disease

The Impact of Different Concentrations of Hemp-Derived Cannabidiol (CBD) Full-spectrum Oil Solutions in the Treatment of Depressive and Anxiety Disorders in Parkinson's Disease Patients.

Parkinson's disease (PD) is a progressive neurodegenerative disorder primarily characterized by motor symptoms such as bradykinesia, rigidity, and tremor. However, non-motor symptoms, particularly anxiety and depression, are also common and substantially affect patients' daily functioning and quality of life. Cannabidiol (CBD), a non-intoxicating constituent of Cannabis sativa, has demonstrated anti-inflammatory, antioxidant, and anxiolytic properties and has shown therapeutic potential in several clinical settings.

The aim of this study was to evaluate the efficacy and safety of full-spectrum CBD oil administered at three different doses (30 mg/day, 60 mg/day, and 300 mg/day) as adjunctive therapy for anxiety and depressive symptoms in patients with Parkinson's disease. This randomized, double-blind, dose-ranging clinical trial enrolled 27 participants with Parkinson's disease and moderate anxiety-depressive symptoms. Participants aged 40 to 70 years, diagnosed with Parkinson's disease at least four years before enrollment and presenting with moderate or greater anxiety-depressive symptoms, were randomly assigned in a 1:1:1 ratio to receive full-spectrum CBD oil at doses of 30 mg/day, 60 mg/day, or 300 mg/day for two months.

Assessments were conducted at baseline, Month 1, Month 2 (end of treatment), and Month 3 (1-month post-treatment follow-up) to evaluate treatment effects and safety after treatment discontinuation. Primary outcomes included changes in anxiety and depression severity measured using the Beck Anxiety Inventory (BAI) and Beck Depression Inventory-I (BDI-I). Secondary and other pre-specified outcomes included assessments of sleep quality, fatigue, cognitive functioning, psychosis symptoms, quality of life, motor and non-motor symptoms of Parkinson's disease, daytime sleepiness, pain, wearable sensor-derived motor assessments, and participant-rated treatment effectiveness.

The CBD oils used in the study were prepared under controlled conditions and tested to verify CBD concentration and the absence of contaminants, including heavy metals and mold contamination.

Participants were monitored throughout the study for adverse events, including somnolence, fatigue, gastrointestinal symptoms, and potential treatment-related safety concerns. The study evaluated the potential role of CBD as an adjunctive treatment for anxiety and depressive symptoms in Parkinson's disease and assessed the safety and tolerability of different CBD dosing regimens.

The duration of participation for each participant was approximately three months, including a two-month treatment period and a one-month follow-up assessment.

Inclusion Criteria:

• Diagnosed Parkinson's Disease according to MDS Clinical Diagnostic Criteria (2015).
• Disease duration ≥4 years before study inclusion.
• Age between 40 and 70 years at enrollment.
• Stable oral medication regimen (including Parkinson's disease medications, antidepressants, and anxiolytics) for at least 1 month prior to inclusion and maintained throughout the study (up to 2 months from inclusion).
• Moderate or higher anxiety-depressive symptoms at baseline (BDI ≥11 points, BAI ≥16 points)

Exclusion Criteria:

• Dementia or cognitive impairment.
• Advanced Parkinson's therapy (DBS, infusion pumps, ablation) or planned initiation within study duration (2 months).
• No caregiver support.
• Pregnancy, breastfeeding, or lack of contraception in women of childbearing potential.
• Neurological or psychiatric disorders affecting evaluation (vascular CNS damage, previous CNS surgery).
• Musculoskeletal conditions preventing motor assessments.
• Active malignancy.
• Cannabinoids use within the last 30 days.
• Use of hepatotoxic drugs or drugs with potential toxic interaction with CBD (e.g., valproic acid, warfarin, haloperidol) within 90 days prior to inclusion.
• Paracetamol intake exceeding 1 g/day during study participation