Many people take medicines every day to manage common health problems like high blood pressure, allergies, or depression. These medicines can help people feel better and live more comfortably.
However, a new study suggests that some of these widely used drugs may have an unexpected effect on the brain, especially in older adults.
Researchers from the University of California, San Diego have found that a group of medicines called anticholinergic drugs may increase the risk of memory and thinking problems over time. Their findings were published in the medical journal Neurology and led by Dr. Lisa Delano-Wood.
Anticholinergic drugs are used to treat a wide range of conditions. People may take them for colds, motion sickness, allergies, high blood pressure, or mental health conditions like depression. Because these drugs are so common, many people use them regularly without thinking much about long-term effects.
These medicines work by blocking a natural chemical in the body called acetylcholine. This chemical plays an important role in how the body works. It helps control muscle movements, supports heart function, and plays a key role in memory and learning.
When this chemical is blocked, it can help reduce certain symptoms, such as runny nose or nausea. But it may also interfere with how the brain processes information.
To better understand the long-term effects, the researchers followed 688 adults for up to 10 years. The average age of the participants was 74. At the start of the study, none of them had memory problems. This allowed the researchers to track changes over time and see how medication use might be linked to new issues with thinking and memory.
The participants were asked about their use of anticholinergic drugs. The study focused on people who took these medicines at least once a week for more than six months. Each year, the participants completed tests to measure their memory and thinking abilities.
The results showed that these medications were quite common. About one in three participants reported using anticholinergic drugs.
On average, those who used them were taking nearly five different drugs in this category. Some commonly used examples included metoprolol and atenolol for high blood pressure, loratadine for allergies, and bupropion for depression.
Over the course of the study, the researchers found a clear pattern. People who took at least one anticholinergic drug had a 47 percent higher risk of developing mild cognitive impairment, often called MCI. This condition involves noticeable problems with memory or thinking that are greater than expected for normal aging.
MCI is important because it is often seen as an early stage of more serious conditions, such as dementia or Alzheimer’s disease. Not everyone with MCI develops dementia, but the risk is higher compared to people without it.
The study also showed that some people faced even greater risks. Participants who already had biological signs linked to Alzheimer’s disease were much more likely to develop memory problems if they used these drugs.
In fact, their risk was about four times higher. People with certain genetic traits linked to Alzheimer’s were also more vulnerable, with about 2.5 times higher risk.
These findings suggest that anticholinergic drugs may have a stronger effect on people who are already at risk for brain-related conditions. For these individuals, the medicines could speed up the decline in memory and thinking.
This is especially important because many of these drugs are easy to access. Some are available over the counter, while others are commonly prescribed. People and even doctors may focus on treating immediate symptoms without considering possible long-term effects on brain health.
The researchers suggest that older adults, especially those with a family history of memory problems or other risk factors, should be careful when using these medications. In many cases, there may be other treatment options that do not affect acetylcholine in the same way.
This study adds to growing evidence that some medications can have hidden effects on the brain. It highlights the importance of reviewing medications regularly, especially as people age. Talking to a doctor or pharmacist can help identify safer alternatives and reduce potential risks.
While these medicines can still be useful and necessary for many people, the key message is awareness. Understanding how different drugs affect the body and brain can help people make better decisions about their health.
More research is still needed to fully understand how these medications influence memory over time. But for now, this study provides an important reminder that even common medicines can have long-term effects that are not always obvious.
If you care about brain health ,please read studies about Vitamin B9 deficiency linked to higher dementia risk, and cranberries could help boost memory.
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