Summary: A new study demonstrates that a specialized oral THC/CBD medical oil formulation significantly and rapidly reduces end-of-life agitation in late-stage dementia patients. Tracking 120 hospice-eligible individuals, the LiBBY trial revealed a significant 6.27-point greater reduction in Cohen-Mansfield Agitation Inventory scores compared to placebo within two weeks. Ultimately, nearly 90% of active-arm patients displayed sustained behavioral improvement with safety profiles matching placebo, offering a highly effective, humane alternative to traditional heavy sedatives.
Key Facts:
- Unprecedented Response Rate: An extraordinary 87.2% of advanced dementia patients treated with the specialized medical THC/CBD compound showed significant behavioral improvement by the end of the 12-week study, a level of success rarely seen in psychiatric trials for dementia.
- Rapid-Acting Calming Effect: The oral oil suspension was formulated to digest quickly, achieving a significant 6.27-point greater reduction in mean agitation scores on the Cohen-Mansfield Agitation Inventory (CMAI) compared to the placebo group within just 14 days.
- Targeted Hospice Focus: The Phase 2 LiBBY trial specifically studied 120 hospice-eligible participants (mean age of 80) across 10 U.S. medical centers, conducting clinical visits entirely in the patients’ homes to avoid the distress of hospital travel.
- Rigorous Medical Supervision: The researchers issued a critical warning that these clinical benefits cannot be replicated with over-the-counter or dispensary cannabis products, which are completely unregulated and vary dangerously in their purity, dosing, and composition.
Source: Georgetown University
In a first-of-its-kind clinical trial, U.S. researchers have found that people with agitation and dementia in late life who took a special medical formulation of two active ingredients found in marijuana – THC and CBD – had significantly less agitation compared to people who received a placebo.
The primary findings of the study were presented July 14, 2026, at the Alzheimer’s Association International Conference in London by Jacobo Mintzer, MD, of the and Medical University of South Carolina and Georgetown University’s Brigid Reynolds, MSN, APRN, ANP-BC.
The study, dubbed the LiBBY trial (Life’s end Benefits of cannaBidiol and tetrahYdrocannabinol), enrolled 120 participants with Alzheimer’s disease or other types of dementia who were hospice-eligible and experiencing agitation. Ten medical centers nationwide conducted the LiBBY study visits at participants’ homes or places of residence. Close to 90% of study participants who received the treatment showed overall improvement after 12 weeks.
“These trial results were extremely impressive and showed a level of response not seen before in clinical trials related to dementia. Rarely do we see close to 90% of patients in a trial respond positively to a new medication,” said Mintzer, the co-lead investigator.
“Agitation affects many people with late-stage dementia, causing symptoms such as restlessness, aggression, and emotional distress that can profoundly impact patients and their caregivers,” explained Reynolds, the co-lead investigator. “Current treatment options are limited and often carry significant side effects, underscoring the need for safer, more effective therapies.”
Medications such as morphine, Valium and Haldol have had limited effectiveness in treating dementia-related agitation and can cause undesirable side effects.
The study was designed to evaluate the effectiveness, safety, and tolerability of a combination of purified tetrahydrocannabinol (THC) and cannabidiol (CBD) given orally in a rapid-acting digestible oil suspension. Participants were randomly assigned to receive either the active combination or placebo. To ensure unbiased results, neither the participants, their caregivers, nor the clinicians knew who received the active treatment. The mean age of participants was 80 years old.
Using a 29-factor agitation assessment survey, the Cohen-Mansfield Agitation Inventory, the researchers compared participants who received the THC/CBD mixture to those receiving a placebo at 2 weeks, the primary outcome due to the fast-acting nature of the drug, and then at 12 weeks.
Each factor related to agitation was rated on a 7-point scale from “never” to “several times per hour” by the caregivers, who were also responsible for giving the medications. After 2 weeks, there was a 6.27-point reduction in mean agitation scores in the THC/CBD group compared with the placebo group; at 12 weeks, there was a significant, sustained reduction in agitation.
A key secondary measurement was the Clinical Global Impression of Change in Behavior assessment. This analysis showed that the THC/CBD group was much less agitated at 2 weeks (83.9% vs 30.5%) and 12 weeks (87.2% vs 23.6%) compared to the placebo group. Adverse event rates, such as infections and gastrointestinal disorders, were comparable between groups (46.7% vs 42.4%) and were expected occurrences in this patient population.
Laura, whose mother participated in the LiBBY trial, said taking part in the study gave her hope that new treatment options may one day improve quality of life for families living with dementia. Although she did not know whether her mother received the study medication or a placebo, she noticed what she described as meaningful changes during visits with her. “She seemed happier,” Laura said. “We experienced joy. There were still moments of connection.”
Although researchers say the results of this trial are encouraging, they caution that the treatment evaluated in the trial differs significantly from commercially available THC and CBD products.
“People should not assume that products available at dispensaries or online are equivalent to what was studied in this trial,” Reynolds said. “The medication used in this research was carefully formulated, manufactured, and administered under close medical supervision. Over-the-counter or commercially available THC and CBD products may vary widely in their composition, quality, and dosing, making them potentially ineffective or even harmful.”
Funding:
The study authors wish to express their gratitude to the LiBBY study participants, their caregivers, and families who generously volunteered their time to make this study possible.
This trial was supported by a National Institutes of Health cooperative agreement grant #R01AG068324-01 and by the Alzheimer’s Association. It is being conducted by the NIH-funded Alzheimer’s Clinical Trial Consortium and coordinated by the University of Southern California’s Epstein Family Alzheimer’s Therapeutic Research Institute, the Medical University of South Carolina, and Georgetown University. The ClinicalTrials.gov ID is NCT05644262.
Key Questions Answered:
A: This is a critical distinction that the research team strongly emphasizes. The formulation used in the LiBBY trial is a highly purified, medical-grade pharmaceutical suspension consisting of specific, precisely calibrated ratios of delta-9-THC and CBD dissolved in a fast-acting digestible oil. Commercial products sold online or at recreational dispensaries are completely unregulated by clinical trial standards, meaning their ingredients, quality, and dosing vary wildly. Using unapproved store-bought oils on frail, late-stage dementia patients can be entirely ineffective or even dangerously toxic.
A: Because the patients enrolled in this study were hospice-eligible and nearing the final stages of life, finding a fast-acting solution was a top priority. Traditional psychiatric medications often take four to six weeks to build up in the system, which is far too slow for someone experiencing acute end-of-life distress. Because this specific oral oil suspension was engineered to digest rapidly, the scientists set the primary benchmark at 2 weeks to see if it could deliver immediate emergency relief. The data proved it did, while the 12-week marker confirmed the relief remained stable over time.
A: Severe agitation is often cited as the single most heartbreaking and exhausting symptom for family caregivers to witness and manage. When a patient can no longer communicate, their distress turns into aggression or non-stop pacing, pushing families to use heavy sedatives that leave the patient completely unresponsive. By safely lowering agitation without wiping out awareness, this purified oil allowed patients to remain present. As one participant’s daughter, Laura, shared, the treatment didn’t offer a cure, but it allowed her mother to feel happier, restoring vital moments of shared connection, dignity, and calm joy in their final days together.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- Journal paper reviewed in full.
- Additional context added by our staff.
About this dementia research news
Author: Karen Teber
Source: Georgetown University Medical Center
Contact: Karen Teber – Georgetown University Medical Center
Image: The image is credited to Neuroscience News
Original Research: The findings will be presented at the Alzheimer’s Association International Conference in London
