How Cannabis Can Reduce the Effects of Alzheimer’s Disease
Alzheimer’s disease (AD) is an illness of the brain characterized by early dementia. Unfortunately, the cause of the disease is not yet known, but it’s not a normal part of aging. There is an increase in abnormal structures called plaques and tangles in the brains of people with Alzheimer’s. The plaques build up between nerve cells and contain deposits of a protein fragment called beta-amyloid. The tangles are twisted fibers of another protein called tau, which form inside dying cells. The plaques and tangles begin forming in areas important in learning and memory and then spreading to other regions. They have also found that levels of acetylcholine are abnormally low in the brains of Alzheimer’s patients. This is a neurotransmitter required for proper nerve function.
NOTE FOR FIRST TIME READERS: Cannabinoids – such as THC, CBD – and terpenes are the main medically active components in cannabis (aka marijuana). For more information on these components and much more about the plant, see our section on the Science of Cannabis.
Antioxidant Properties of Cannabis Could Slow Alzheimer’s Disease
Research has shown that cannabinoids work as an antioxidant and help protect nerve cells from long-term damage or degeneration. There have also been several studies in recent years looking at their effect on Alzheimer’s. The findings show that cannabinoids may slow the progression of the disease. In addition, THC has been shown to help appetite and weight gain in Alzheimer’s patients with anorexia.
Cannabis Reduces Amyloid Plaque Formation
In a study by scientists at Scripps Institute, they have found that THC slows the formation of amyloid plaque, which is the main indicator (or marker) for Alzheimer’s disease. In fact, the study said that THC is “a considerably superior inhibitor of [amyloid plaque] aggregation” as compared to other drugs used for treating the disease. THC affects the enzyme (acetylcholinesterase) that causes the formation of amyloid plaque in the brains of Alzheimer patients.
While generally very pleasant, THC-rich cannabis can be disorienting because of its psychoactive properties. That’s why it should be used with caution in people suffering from Alzheimer’s Disease. CBD-rich strains (more info in Science of Cannabis) are often mixed with THC-rich cannabis to reduce psychoactive properties.
Anti-Inflammatory Benefits of CBD Could Also Treat Alzheimer’s
Another study compared brain tissue from people who had Alzheimer’s before they died with brains from those of similar age who didn’t have the disease. They found that cannabinoid receptors in diseased brain tissue had dramatically lost their protective effect. And because cannabinoids offer both anti-inflammatory and nerve protection benefits, they concluded that cannabis could very well be a powerful therapeutic treatment for this devastating disease.
No clinical trials with humans have been published for the study of cannabis and AD, so we don’t know dosage guidelines for this condition. In one recent small study of ten patients given medical cannabis, significant decrease was found in delusions, agitation, aggression, irritability, apathy, sleep and caregiver distress.
How You Can Use CBD To Supplement Alzheimer’s Disease Treatment
To treat this condition, you should choose the type of cannabis based on the specific benefits it offers. For Alzheimer’s both CBD and THC are effective because of their antioxidant, neuroprotectant properties. CBD is successfully used to decrease agitation in AD and other dementia patients, and to treat “Sundowners syndrome.” Some THC added to the mix may help combat fatigue and depression, but should be used with care. In general, CBD rich cannabis is preferred for AD patients rather than THC due to decreased psychoactive effects. Dosage for neuroprotection may go as high as 25 mg of CBD rich cannabis 2-3 times/day, but to decrease agitation, but a lower dose of 5 mg, by tincture or edible 1-2 times/day may suffice for symptom control.
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