Many people take common medications to help with allergies, high blood pressure, depression, or motion sickness.
These drugs are often trusted and used for years. But a new study from the University of California, San Diego, shows that some of these medications might harm memory and thinking skills, especially in older adults or people at risk for Alzheimer’s disease.
These medications are called anticholinergic drugs. They work by blocking a chemical in the body called acetylcholine. This chemical helps control things like muscle movement, heart rate, and, most importantly, memory and learning. When this chemical is blocked, the drugs can help with certain illnesses, but they may also affect how the brain works over time.
In the study, researchers followed 688 people who were around 74 years old. At the start, none of them had problems with memory or thinking. They were asked if they had taken any anticholinergic drugs at least once a week for more than six months. The researchers then checked their memory and thinking each year for up to 10 years.
About one-third of the people had been taking these drugs. On average, they were using nearly five different types. Common ones included metoprolol and atenolol for high blood pressure, loratadine for allergies, and bupropion for depression.
The results were surprising. People who took at least one of these drugs were 47% more likely to develop mild cognitive impairment, or MCI, compared to those who did not take them. MCI is a condition where someone has more memory problems than expected for their age, and it can sometimes lead to dementia or Alzheimer’s disease.
The risk was even higher for people who already had signs of Alzheimer’s in their spinal fluid. If they took anticholinergic drugs, they were four times more likely to develop memory problems. People with genes that made them more likely to get Alzheimer’s were also 2.5 times more likely to have memory decline if they used these drugs.
This research shows that using these drugs could speed up memory loss in people who are already at risk. This is worrying because these medications are very common and are often used without much thought about the effects on the brain.
The scientists say that people, especially older adults, should talk to their doctors about other options. There might be safer ways to treat allergies, depression, or high blood pressure without using anticholinergic drugs. Being careful about what medicines we take could help protect our memory and thinking abilities as we age.
This study is part of a larger group of research suggesting that the drugs we take for one health problem might hurt us in other ways. For example, some blood pressure medicines can also affect the brain if not chosen carefully.
If you or someone you know is taking these kinds of medications and is worried about memory problems, it’s a good idea to speak with a doctor. They can help find safer choices.
This research was led by Lisa Delano-Wood and published in the journal Neurology.
If you care about Alzheimer’s disease, please read studies about New Alzheimer’s treatment: anti-inflammatory drug may prevent memory loss and findings of The diabetes drug surprise: a possible shield against Alzheimer’s?
For more about brain health, please read studies about Scientists find connection between fungus and Alzheimer’s disease and findings of Scientists find links between COVID-19 and Alzheimer’s disease.
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