Free Health Updates
Skip to main content
Table of Contents
< All Topics
Print

Is Cannabis’ THC or CBD Better for Agitation in Dementia? 

Posted
Updated
ByMy Patient Advice
Author: Julia Sutton, MSc | Reviewed by: Dr. Clarissa Morton, PharmD

As families and clinicians search for safer ways to calm agitation in dementia, attention has turned to cannabis-based products, especially those containing THC (tetrahydrocannabinol) and CBD (cannabidiol). But current evidence still paints a cautious picture. 

Can medical cannabis be accessed legally for women’s health?

What The Research Shows 

Recent studies suggest that CBD-rich oils may ease agitation and improve sleep more than placebo. A 2022 randomised controlled trial in Frontiers in Medicine found that CBD-dominant cannabis oil reduced behavioural disturbances in dementia without serious side effects, though around one-third of participants also received some THC, making it difficult to separate each compound’s effects. 

Systematic reviews, including a 2023 BMJ umbrella review by Solmi and colleagues, and a 2021 meta-analysis by Outen et al. (PMC), report little consistent benefit from THC alone and highlight possible worsening of confusion or hallucinations. Mixed formulations containing both THC and CBD, often in 1:1 or 1:2 ratios, appear tolerable in small, short-term studies, but results remain inconsistent across trials. 

What The Guidelines Say 

According to NICE guidance (NG144, updated 2025) and the NHS, cannabis-based medicinal products, including THC, CBD, and Sativex, should not be prescribed for behavioural symptoms of dementia outside of research settings. The WHO has not endorsed cannabinoids for dementia symptom management either. 

In the UK, prescribing such products for agitation is currently lawful only within authorised clinical trials, such as the ongoing STAND study at King’s College London. 

Safety And Risks 

Both THC and CBD can cause drowsiness, dizziness, and falls, particularly in frail older adults. However, THC poses additional risks of psychosis, hallucinations, and worsening cognition. CBD generally shows a better safety profile and may even reduce some of THC’s negative effects, but neither should be considered risk-free. 

Expert Consensus 

The Alzheimer’s Society and Mayo Clinic both emphasise that there is no evidence cannabis prevents or reverses dementia, and research on agitation relief remains preliminary. Geriatric psychiatry experts agree that cannabinoids should be used only in carefully monitored research trials, not routine clinical care. 

Clinical Bottom Line 

  • CBD-rich oils may help agitation or sleep in dementia, but results are inconsistent. 
  • THC alone offers no clear benefit and may worsen confusion or psychosis. 
  • NICE and NHS do not recommend cannabis-based products for dementia symptoms. 
  • Prescribing cannabinoids for agitation is only permitted in research settings. 
  • CBD is likely safer than THC but should not be used outside clinical trials. 

About AlleviMed 

Organisations such as AlleviMed provide educational information about how UK eligibility for medical cannabis is assessed, helping families understand the legal and clinical frameworks surrounding CBMPs, but do not offer prescribing or treatment services. 

Takeaway 

At present, CBD appears safer than THC for agitation in dementia, but neither compound has robust clinical proof to support everyday use. Both remain research-only options under UK law. According to NICE and the Alzheimer’s Society, best practice still lies in non-drug behavioural approaches, with cannabinoids reserved for scientific study, not standard care. 

Julia Sutton, MSc
Author

Julia Sutton is a clinical psychologist with a Master’s in Clinical Psychology and experience providing psychological assessment and therapy to adolescents and adults. Skilled in CBT, client-centered therapy, and evidence-based interventions, she has worked with conditions including depression, anxiety, bipolar disorder, and conversion disorder. She also has experience in child psychology, conducting psycho-educational evaluations and developing tailored treatment plans to improve learning and well-being.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the author's privacy. 

Dr. Clarissa Morton, PharmD
Reviewer

Dr. Clarissa Morton is a licensed pharmacist with a Doctor of Pharmacy degree and experience across hospital, community, and industrial pharmacy. She has worked in emergency, outpatient, and inpatient pharmacy settings, providing patient counseling, dispensing medications, and ensuring regulatory compliance. Alongside her pharmacy expertise, she has worked as a Support Plan & Risk Assessment (SPRA) officer and in medical coding, applying knowledge of medical terminology, EMIS, and SystmOne software to deliver accurate, compliant healthcare documentation. Her skills span medication safety, regulatory standards, healthcare data management, and statistical reporting.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the reviewers's privacy. 

Categories