Can Cannabis Increase Falls by Causing Sedation in Dementia?

PostedMarch 12, 2026

UpdatedMarch 12, 2026

ByMy Patient Advice

Author: Julia Sutton, MSc | Reviewed by: Dr. Clarissa Morton, PharmD

As medical cannabis gains attention for managing behavioural symptoms in dementia, safety remains a critical concern, especially sedation, dizziness, and fall risk. While some evidence suggests cannabis can calm agitation, studies between 2020 and 2025 consistently report that THC, the psychoactive compound in cannabis, is the main contributor to these side effects. CBD appears to be better tolerated.

Why Sedation Matters

Older adults with dementia are particularly vulnerable to the effects of sedation and postural instability. According to NHS medical cannabis guidance, cannabinoids can cause sleepiness, slower reaction times, and reduced concentration, all of which may increase the risk of falls.

The Age and Ageing 2024 meta-analysis involving over 6,600 participants, found that THC and THC: CBD products increased rates of dizziness, somnolence, and fatigue by almost 19 cases per 100 users. Although serious injuries were uncommon, researchers concluded that sedation and balance problems were dose related.

THC vs CBD: What the Evidence Shows

THC activates CB1 receptors in the brain, reducing alertness and coordination. This mechanism underlies its calming effect but also its tendency to slow reflexes and impair balance. CBD, by contrast, acts through serotonin (5-HT1A) and adenosine pathways, providing mild relaxation without significant sedation.

Clinical data from dementia trials reinforce this difference:

In the UK STAND trial (2025) using a THC: CBD spray, mild sedation and dizziness were reported, though no serious falls occurred (PMC12143470).

In the Avidekel CBD trial (2022), sedation rates were minimal, with no increase in falls (PubMed 36148467).

A Swiss study of THC: CBD oil reported drowsiness and unsteady gait in a few participants, particularly at higher THC doses (PubMed 36247984).

What NICE And Alzheimer’s Society Say

According to NICE guidance NG97 and NICE NG144, cannabinoids are not recommended for dementia because of limited evidence and potential for sedation and confusion. The Alzheimer’s Society also warns that dizziness and drowsiness are common side effects, especially when cannabis is combined with other sedating medicines.

Clinical Bottom Line

THC increases sedation and dizziness, which may lead to falls.

CBD is better tolerated, with minimal motor or balance effects.

Falls are uncommon but more likely in frail or polypharmacy patients.

NICE and NHS urge caution and recommend specialist oversight for any cannabinoid use in dementia.

Educational Context: AlleviMed

AlleviMed provides public education on how cannabis-based medicinal products are regulated in the UK under MHRA and Home Office frameworks. It clarifies that cannabis is not licensed for dementia symptoms and should be used only under specialist supervision.

Takeaway

While THC-containing cannabis may help calm agitation, it can also increase sedation and fall risk in people with dementia. CBD-based formulations appear safer but remain under investigation. According to NHS, NICE, and Alzheimer’s Society guidance, non-drug strategies and careful medication review remain the best approach to reducing falls and maintaining safety in dementia 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.