Synthetic tetrahydrocannabinol, available as dronabinol, holds a credible position among these sometimes effective pharmacological approaches, although both positive and negative results have been reported.11-13 Antipsychotic medications, still frequently prescribed, are recognized as potentially harmful and of limited clinical value for many agitated, cognitively impaired patients.14 The FDA-approved cognitive enhancers, memantine and the cholinesterase inhibitors, are not regarded as valuable treatments for acute agitation.
Marijuana: effective and safe?
The jury is still out on medical marijuana’s role in the treatment ofAlzheimer disease and other major neurocognitive disorders. Anorexia, nausea, anxiety, depression, or pain might be reasonable indications in selected patients. The benefits of such use must be weighed against potential risks. Some research suggests that marijuana’s active alkaloids, the cannabinoids, can mitigate Alzheimer disease progression through neuroprotective blockade of microglial activation.15
The more commonly used forms of marijuana appear to remain untested as treatments for agitation in Alzheimer disease.
Cannabis has been reported to have adverse acute and non-acute effects on cognitive functions, which might outweigh its therapeutic benefits.16 Furthermore, marijuana use has been associated with hallucinations and adverse effects on mood and memory as well as unpleasant physical symptoms, including blurred vision, dizziness, dry mouth and eyes, tachycardia, somnolence, urinary retention, and changes in blood pressure.
Marijuana interacts through pharmacokinetic and pharmacodynamic mechanisms with a large variety of prescribed psychiatric medications, including SSRIs, TCAs, and lithium. It has an additive effect when used in conjunction with other CNS depressants.17 One case report attributed increased bleeding risk to the combined use of marijuana and warfarin, and another case report attributed a man’s myocardial infarction to the concurrent use of marijuana with sildenafil.18,19 Needless to say, these potential complications could seriously complicate the treatment of a person with dementia.
MORE ABOUT JAMES M. ELLISON, MD, MPH
Formerly Director of Geriatric Psychiatry at McLean Hospital in Belmont, Massachusetts, I recently re-located to Wilmington, Delaware, where I am privileged to serve as the first Swank Foundation Endowed Chair in Memory Care and Geriatrics. In that capacity, I am consultant to a team of geriatricians who have helped me experience the great value of interdisciplinary and collaborative care.
I am the proud father of 2 teenage boys. I wish for them as much career satisfaction, whatever they choose to pursue, as I have found in psychiatry.
Disclosures:
Dr. Ellison is Professor of Psychiatry and Human Behavior, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA; and Swank Foundation Endowed Chair in Memory Care and Geriatrics at Christiana Care in Wilmington, DE. He reports no conflicts of interest concerning the subject matter of this article.
Acknowledgment-This article is from the Committee on Aging of the Group for the Advancement of Psychiatry (GAP): Robert P. Roca, MD, Chair; James M. Ellison, MD; Warachal Faison, MD; Helen Kyomen, MD; Susan Lehman, MD; Ben Liptzin, MD; Marsden McGuire, MD; Keith Meador, MD; Robert Rohrbaugh, MD; and Ken Sakauye, MD. The GAP, American psychiatry’s think tank, informs and educates mental health professionals, policy makers, and the public at large.
References:
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