19 States Allow Medical Cannabis for Alzheimer's Agitation — Despite Almost No Evidence It Works | Research

The takeaway

Half of U.S. states with medical cannabis programs list Alzheimer's disease as a qualifying condition, but AD accounts for less than 1% of medical cannabis certifications, and clinical evidence supporting its use is sparse.

Read this if you care for someone with Alzheimer's and have considered medical cannabis for agitation — access is widespread but evidence of benefit is limited.

What the researchers found

Agitation in Alzheimer's disease is a devastating symptom affecting up to 70% of patients, and current pharmaceutical options carry significant risks, including increased mortality from antipsychotics. Medical cannabis has been proposed as an alternative, and this study mapped the current state of access.

The numbers tell an interesting story. Of 38 states allowing medical cannabis, 19 (50%) include Alzheimer's disease as a qualifying condition. But actual uptake is minimal — AD accounts for less than 1% of medical cannabis certifications. There's a large gap between legal access and actual use.

The reason for low uptake is likely multifactorial: dementia patients often can't self-advocate for or self-manage medical cannabis, caregivers may be reluctant, clinicians lack guidance on dosing and monitoring, and the evidence base supporting cannabis for AD agitation is thin.

An additional finding is that AD as a qualifying condition appears to be declining in states that have legalized recreational cannabis — suggesting that the medical program pathway becomes less relevant when cannabis is available without medical certification.

The mismatch between widespread legal access and minimal evidence of efficacy creates a policy puzzle: states have made cannabis available for AD based on theoretical benefit, but the clinical trial data to support or refute this decision largely doesn't exist.

Why it matters

This mapping exercise reveals a broader pattern in medical cannabis policy: conditions are often added to qualifying lists based on theoretical plausibility rather than clinical evidence. For Alzheimer's caregivers and clinicians, the finding that 19 states allow medical cannabis for AD is relevant — but so is the finding that almost nobody uses it, and the evidence that it helps is limited.

The numbers in context

38 states allow medical cannabis. 19 (50%) include AD as a qualifying condition. AD accounts for <1% of medical cannabis certifications. AD certifications appear to be declining in states with legal recreational cannabis.

How the study worked

Observational study examining regulatory agencies' publicly available online reports regarding medical cannabis access across U.S. states in 2024-2025, specifically assessing AD as a qualifying condition. Analyzed certification data where available to determine what proportion of medical cannabis users qualify through AD.

Who was studied

38 states in the US regarding medical cannabis access for Alzheimer's Disease.

What this study cannot tell us

Data comes from publicly available regulatory reports, which vary in completeness and detail across states. Actual cannabis use by AD patients may differ from certification numbers (patients may obtain cannabis through recreational channels or caregiver purchases). The study doesn't assess clinical outcomes — only access and uptake. State-by-state policy differences make generalization difficult.

How to read the evidence

Regulatory landscape analysis using publicly available data. Valuable for understanding policy-evidence gaps, but doesn't generate clinical evidence about whether cannabis helps AD agitation.

When this study was published

Published in 2025. The landscape of medical cannabis qualifying conditions continues to evolve.

The bigger picture

This connects directly to RTHC-00085 (THC/CBD for dementia behavioral symptoms, the Swiss 2-year pilot) and RTHC-00080 (cannabinoids for Parkinson's and dementia). The Swiss pilot showed safety and suggestive efficacy in 19 patients, but that's essentially the entire evidence base. Meanwhile, 19 states have already made cannabis available for AD. The gap between policy speed and evidence development is a recurring theme in cannabis regulation.

Replication

Not stated in abstract.

Funding

Not reported in abstract.

Conflicts of interest

Not reported in abstract.

Questions still open

Would a well-designed clinical trial show cannabis benefits AD agitation enough to justify the widespread qualifying condition status? Is the low uptake a failure of the medical cannabis system to serve dementia patients, or an appropriate response to weak evidence? As recreational legalization spreads, does the medical cannabis qualifying condition model become irrelevant for all conditions?

Read the original research

Agitation in Alzheimer's Disease as a Qualifying Condition for Medical Cannabis in the United States: A Brief Report on Current Trends.

The American journal of geriatric psychiatry : official journal of the American Association for Geriatric Psychiatry

The American Journal of Geriatric Psychiatry is a reputable journal focusing on mental health issues in older adults.

View on PubMed ↗Publisher’s paper ↗

Citation

Bonar, Erin E; Tan, Chiu Yi; Patyk, Adam; Lei, Lianlian; Maust, Donovan T. (2025). Agitation in Alzheimer's Disease as a Qualifying Condition for Medical Cannabis in the United States: A Brief Report on Current Trends.. The American journal of geriatric psychiatry : official journal of the American Association for Geriatric Psychiatry. https://doi.org/10.1016/j.jagp.2025.06.003