Rationale and Comments
Anticholinergics (e.g., overactive bladder medications, first-generation antihistamines) competitively inhibit binding of the neurotransmitter acetylcholine, thus reducing the effects of acetylcholine. Cholinesterase inhibitors, used in the treatment of dementia, act by blocking the enzyme acetylcholinesterase, thereby inhibiting acetylcholine degradation. Therefore, pharmacologic actions of anticholinergics and cholinesterase inhibitors oppose each other. Concomitant use of anticholinergics with cholinesterase inhibitors reduces the effectiveness of antidementia drugs, the benefits of which are modest at best; concomitant use increases the risk of adverse effects of anticholinergics and may also increase the rate of functional and cognitive decline. Medications with anticholinergic properties are commonly prescribed to treat comorbidities associated with dementia and sometimes the adverse effects of cholinesterase inhibitors. Patients with dementia are sensitive to cognitive impairment induced by medications with anticholinergic properties. In general, it has been recognized that anticholinergics adversely affect cognition in older patients and even more so with concomitant dementia diagnosis.
- American Society of Consultant Pharmacists
- Geriatric Medicine
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- 2019 American Geriatrics Society Beers Criteria® Update Expert Panel. American Geriatrics Society 2019 updated AGS Beers Criteria for potentially inappropriate medication use in older adults. J Am Geriatr Soc. 2019;67(4):674-694.