Many people take medications every day for common problems like allergies, high blood pressure, colds, or even depression.
But a new study from the University of California, San Diego, shows that some of these drugs might quietly harm the brain over time—especially for older adults and people at risk for Alzheimer’s disease.
The medications in question are called anticholinergic drugs. These are used to block a chemical in the body called acetylcholine, which helps control muscles and some brain functions, including memory.
These drugs are found in many places: in pills for motion sickness, bladder issues, sleep aids, allergy medications, and even some antidepressants.
Researchers wanted to understand if taking these medications over a long period could be connected to memory problems. They followed 688 older adults for up to 10 years. At the beginning of the study, none of them had any memory or thinking issues.
The average age was 74. About one-third of them were taking at least one anticholinergic drug, and many were taking several—on average, nearly five different medications.
What the researchers discovered was concerning. People who took these drugs were 47% more likely to develop mild cognitive impairment, which means problems with memory or thinking that are more than normal aging but not as serious as dementia. This condition can be an early warning sign for Alzheimer’s disease.
For people who already had signs of Alzheimer’s disease in their spinal fluid—a marker that shows changes in the brain—the risk was even higher.
These individuals were four times more likely to develop thinking problems if they were also taking anticholinergic drugs. Even those with just a genetic risk for Alzheimer’s were about 2.5 times more likely to develop memory issues when using these medications.
This means that for people who already have a higher risk of Alzheimer’s—due to their genes or early brain changes—these medications might be especially harmful.
The researchers believe that it may be helpful for people to avoid or reduce the use of these medications before any signs of memory loss appear. This could help protect the brain and delay or prevent problems with thinking and memory.
This study is important because it shows that common medicines, which may seem harmless, could actually play a role in long-term brain health. It also suggests that doctors should think more carefully before giving these drugs, especially to older adults or those at risk for Alzheimer’s.
While more research is needed, this study could lead to changes in the way some medications are prescribed. It reminds us that what we take for our bodies can also affect our minds—and we should pay attention to both.
If you care about brain health, please read studies about Vitamin B9 deficiency linked to higher dementia risk, and cranberries could help boost memory.
For more health information, please see recent studies about heartburn drugs that could increase risk of dementia, and results showing this MIND diet may protect your cognitive function, prevent dementia.
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