28/12/2025
Trials show small cannabis doses can slow early Alzheimer’s decline.
A small randomized, double-blind, placebo-controlled trial in Brazil has found that microdoses of cannabis extract may help stabilize cognitive decline in people with mild Alzheimer’s disease. Twenty-four patients aged 60 to 80 received a daily oil containing extremely low, sub-psychoactive doses of THC and CBD (0.3 mg of each) or placebo for 24 weeks. Those given the cannabis extract maintained their scores on the Mini-Mental State Examination, a standard cognitive test, while the placebo group showed the expected gradual deterioration. The difference—about two to three points on a 30-point scale—was modest but clinically meaningful and was achieved without the “high” or an increase in adverse effects, suggesting a potential therapeutic window where cannabis can act on the brain without altering consciousness.
The study builds on earlier animal research and a long single-patient observation suggesting that very low doses of cannabinoids can restore aspects of brain function in aging, possibly by supporting the endocannabinoid system and reducing brain inflammation. However, the authors stress that the trial is preliminary: the sample was small, the benefit was limited to one cognitive measure, and no improvements were seen in mood, general health, or quality of life. Larger, longer studies that include biological markers such as neuroimaging and inflammatory measures are needed before concluding that microdosed cannabis can truly slow Alzheimer’s progression. For now, the findings point to a promising, culturally more acceptable “cannabis without the high” approach, but they do not yet justify broad clinical use.
References (APA style)
Pamplona, F. (2025, December 19). Microdosing cannabis pauses Alzheimer’s decline in unprecedented trial. ScienceAlert.
Pamplona, F., et al. (2025). Microdoses of cannabis extract in patients with mild Alzheimer’s disease: A randomized, double-blind, placebo-controlled trial. Journal of Alzheimer’s Disease.
