When people take medicine for everyday health problems—like allergies, high blood pressure, or bladder issues—they usually expect to feel better, not worse. But researchers at the University of California, San Diego, have found something surprising and a bit worrying: some of these common medicines might actually harm your memory over time.
The study focused on a group of medicines called anticholinergic drugs. These medicines are used for many different health conditions. Some are taken to treat allergies, others to manage high blood pressure, Parkinson’s disease, depression, or problems with the bladder.
There are about 100 different anticholinergic drugs, and some of them can be bought without a prescription. Others are only available if a doctor prescribes them.
The researchers studied 688 older adults, with an average age of 74. None of them had memory or thinking problems at the beginning of the study. They were followed for up to ten years, and during this time, their brain health and memory were checked once a year.
About one-third of these people had been taking at least one anticholinergic drug regularly—defined in the study as at least once a week for six months or more.
These drugs included common ones like Metoprolol and Atenolol (used for blood pressure), Loratadine (used for allergies), and Bupropion (used for depression). On average, the people in this group were taking about five different anticholinergic medicines at the same time.
After years of monitoring, the researchers found that people taking at least one anticholinergic drug had a 47% higher chance of developing memory problems than those who weren’t taking any of these medicines. In other words, nearly half of those on these drugs were more likely to experience trouble remembering things as they got older.
Even more concerning was what happened to people who already showed some early signs of Alzheimer’s disease at the start of the study. Those people were four times more likely to have worsening memory problems if they were taking anticholinergic drugs.
And for those who had genes that made them more likely to get Alzheimer’s, taking these drugs made them 2.5 times more likely to have memory issues.
Memory problems are often one of the first signs of serious brain diseases like Alzheimer’s. So, these results suggest that we should be careful when using certain medicines, especially in older adults or those who already have risk factors for memory decline.
This research raises big questions about how we treat conditions like high blood pressure and allergies. Sometimes, lifestyle changes—like improving diet or exercise—might be a safer first step.
For example, eating foods like beetroot has been shown to help lower blood pressure naturally. It might be better for some people to try those options before jumping straight into long-term use of medicine.
Dr. Lisa Delano-Wood, the lead researcher, says the goal isn’t to scare people away from taking necessary medication. Instead, the study highlights the importance of understanding possible side effects and making informed choices.
Doctors and patients may need to work together more closely to choose the safest treatment options—especially when it comes to protecting brain health as we age.
The results of the study were published in the journal Neurology, and they add to growing evidence that even widely used medications can have unexpected long-term effects. As people live longer, paying attention to how treatments affect memory and thinking will become even more important.
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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