Common over-the counter and prescription medications known as anticholinergics can cause cognitive impairment and can lead to death, a new study says.
The group includes over-the-counter products containing diphenhydramine, prescription sleep aids and incontinence treatments, many of which are frequently taken by older adults, the researchers said.
"Physicians should review with older patients all the over-the-counter and prescription drugs they are taking to determine exposure," said study researcher Dr. Malaz Boustani, an associate professor and aging researcher at Indiana University School of Medicine.
Older adults and cognitive function
The two-year study looked at the affect of these medications on 13,000 men and women age 65, and is part of a larger United Kingdom-based study looking at health and cognitive function in older adults.
Anticholinergics affect the brain by blocking the neurotransmitter acetylcholine.
The drugs include over-the-counter medications such as those sold under the brand names Benadryl, Dramamine, Excedrin PM, Nytol, Sominex, Tylenol PM and Unisom, the researchers said. Other anticholinergic drugs, such as Paxil, Detrol, Demerol and Elavil are available by prescription.
Medications with anticholinergic effects are used for many diseases, including hypertension and congestive heart failure. The study found that those who were older, had lower incomes and a greater number of health conditions were more likely to use these medications. Women were more likely to report taking anticholinergic medications, due to the greater number of health conditions reported by women than by men.
More work needed
"We looked at drugs with either moderate [or] severe anticholinergic activity. After adjusting for age, sex, baseline mental status, education, income level, number of non-anticholinergic medications and health conditions, we found that taking anticholinergic medications was linked to cognitive impairment and for the first time to death," said study researcher Dr. Chris Fox, a psychiatrist at the University of East Anglia.
"We need follow-up to determine the degree to which anticholinergics are being prescribed for diseases with significant risk of death and the impact of that on our findings," Fox said.
The study was published online today (June 24) in the Journal of the American Geriatrics Society.
Pass it on: Anticholinergics may impair thinking and increase the risk of death.
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.