Medical Marijuana and Alzheimer’s disease

Alzheimer’s disease is a progressive neurodegenerative disorder with no known cause. It is characterized by a progressive deterioration of memory and overall cognitive functioning. Many patients have aggressive behavior, agitation, appetite loss, depression and difficulty walking. In 2006, there were over 26 million people worldwide suffering with Alzheimer’s disease.
There is central nervous dysfunction in Alzheimer’s patients with nerve cell death and broken connections between nerve cells. Brain biopsies of Alzheimer’s patients show hardened protein deposits called amyloid plaques.

There are a few FDA-approved medications to treat symptoms of the disease but none of these improve the long-term prognosis or stop the formation of the plaques.

There are a number of published scientific studies that have shown that cannabis may provide symptomatic relief of symptoms for these patients and also may limit the formation of new plaques in the brain. Both of the major cannabinoids in cannabis, THC and CBD, have been found to have benefits for patients suffering with Alzheimer’s disease.

In 2006, researchers at Scripps Research Institute reported that delta-9-THC inhibited the enzyme responsible for the aggregation of amyloid plaques. Other studies showed that cannabidiol, a cannabinoid medicine found in the cannabis plant, and WIN-55,212-2, a synthetic cannabinoid made in the laboratory, both helped to prevent brain-cell death that occurs from exposure to amyloid plaques and also helped to improve memory.

In an open-label pilot study, patients with Alzheimer’s disease received 2.5 mg of synthetic THC over a two-week period. These patients had reduced agitation and reduced nighttime activity. Another study reported that Alzheimer’s patients who were given cannabinoids had improved weight gain and improved mood.

For many patients suffering with Alzheimer's disease, and for their families, any possible delay in progression combined with improvement of symptoms would be welcomed. More studies of the use of medical cannabis in Alzheimer's patients are warranted as the preliminary studies show real promise and may be key to finding a cure.

References:

Eubanks, L., et al. A Molecular Link between the Active Component of marijuana and Alzheimer’s Disease Pathology. Molecular Pharmaceutics 3 (2006): 773-77

Iuvone, T., et al. Neuroprotective Effect of Cannabidiol, a Non-psychoactive Component from Cannabis Sativa, on Beta-amyloid-induced Toxicity in PC12 Cells. Journal of Neurochemistry 89 (2004): 134-41

Marchalant, Y., et al. Cannabinoid Receptor Stimulation is Anti-inflammatory and Improves Memory in Old Rats. Neurobiology of Aging 29 (2008): 1894-901

Marchalant, Y., et al. Anti-Inflammatory Property of the Cannabinoid Agonist WIN-55,212-2 in a Rodent Model of Brain Inflammation. Neuroscience 144 (2007): 1516-22

Walther, S., et al. Delta-9-tetrahydrocannabinol for Nighttime Agitation in Severe Dementia. Psychopharmacology 185 (2006): 524-8

Volicer, L., et al. Effects of Dronabinol on Anorexia and Disturbed Behavior in Patients with Alzheimer’s Disease. International Journal of Geriatric Psychiatry 12 (1997): 913-19