(RxWiki News) Medications for allergies, depression and incontinence can be lifesavers. However, they may have some surprising effects on mental health.
A new study found that some older adults who took anticholinergic medications in high doses or for long periods of time had an increased risk of dementia.
"Prescribers should be aware of this potential association when considering anticholinergics for their older patients and should consider alternatives when possible," wrote lead study author Shelly L. Gray, PharmD, of the University of Washington in Seattle, and colleagues. "For conditions with no therapeutic alternatives, prescribers should use the lowest effective dose and discontinue therapy if ineffective."
Dr. Gray and colleagues reviewed pharmacy data for almost 3,500 patients older than 65 in the Seattle area.
Almost a quarter of patients who used anticholinergics developed dementia during the follow-up period. Of those, almost 80 percent developed Alzheimer's disease, Dr. Gray and team found.
Dementia is a loss of brain function that affects memory, judgment and behavior. Alzheimer's disease is the most common form of dementia, according to the Alzheimer's Association. Symptoms include depression, apathy and loss of memory.
Doctors prescribe these anticholinergics for various conditions, such as allergies, incontinence, depression and sleep disorders. They include antidepressants like Sinequan and antihistamines like Benadryl and Atarax.
"For most conditions, there are alternatives to anticholinergics," Dr. Gray told dailyRx News. "Older adults should avoid using over-the-counter sleep aids which often include strong anticholinergics."
When there are no alternatives, older patients should use the minimum effective dose, Dr. Gray said.
"For older adults with urinary incontinence, nondrug therapy should be tried first," Dr. Gray said. "However, if nondrug therapy does not provide full improvement in symptoms and anticholinergic therapy is warranted, health care providers should use the lowest effective dose, monitor the therapy regularly to ensure it's working, and stop the therapy if it's ineffective."
Older patients are usually more sensitive than younger adults to the effects of these medications, according to the Mayo Clinic. Side effects may include drowsiness, confusion, memory loss and restlessness.
Dr. Gray said this study did not show whether anticholinergics caused dementia. It only found a relationship between dementia and these medications.
However, older patients should limit their use of these medications when possible to reduce risks, she said.
This study was published Jan. 26 in JAMA Internal Medicine.
The National Institute on Aging and the Branta Foundation funded this research. Study authors received grants and other funding from companies like Pfizer, Merck, Amgen and UpToDate.