As the world’s population ages, the number of people living with dementias such as Alzheimer’s disease continues to rise.
Given the lack of curative treatments and the limited effectiveness of existing medications, interest in new therapeutic approaches is growing. Among these are cannabinoids derived from the cannabis plant.
A small Brazilian study published in the Journal of Alzheimer’s Disease investigated the effects of microdoses of cannabis extract in patients with mild Alzheimer’s disease. The results showed positive effects without the psychoactive “high” typically associated with cannabis.
The Logic of Microdosing
The study, led by Professor Francisney Nascimento and colleagues at the Federal University of Latin American Integration (UNILA), recruited 24 elderly patients aged 60 to 80 who had been diagnosed with mild Alzheimer’s disease.
Participants were given a daily oil prepared from a cannabis extract containing THC and CBD in similar proportions and at extremely low concentrations—0.3 milligrams of each cannabinoid. These sub-psychoactive doses are not associated with the intoxicating effects of recreational cannabis use.
The extract was donated by ABRACE, Brazil’s largest patient association, and the study received no funding from cannabis companies or other commercial sources.
The term “microdosing” is most often associated with the recreational use of psychedelics, and given the tiny quantities involved, it may seem unlikely that such doses could have measurable effects. Doses below 1 milligram of cannabinoids are rarely reported in clinical practice.
However, the researchers’ decision was based on earlier evidence. In 2017, a research group led by Andreas Zimmer and Andras Bilkei-Gorzo demonstrated that very low doses of THC restored cognitive function in elderly mice. The treatment reversed age-related gene expression patterns and increased synaptic density in the hippocampus to levels comparable to those seen in younger animals.
Subsequent animal studies showed that the endocannabinoid system—important for neuroprotection and the regulation of normal brain activity, including memory—naturally declines with age.
From a Single Patient to a Clinical Trial
Next page
