Many people take medications every day to treat common health problems such as allergies, high blood pressure, or bladder issues. These medicines can help people feel better and manage their symptoms.
However, new research suggests that some widely used drugs may have an unexpected effect on brain health, especially in older adults.
A study from the University of California, San Diego, has found that a group of medicines known as anticholinergic drugs may increase the risk of memory problems. The findings suggest that people who regularly use these medications may be more likely to develop difficulties with memory and thinking as they age.
Anticholinergic drugs are commonly used to treat a wide range of conditions. Doctors prescribe them for allergies, colds, bladder control problems, high blood pressure, Parkinson’s disease, and several other health issues.
Some of these medicines can be purchased over the counter at pharmacies, while others require a prescription from a doctor.
These medications work by blocking a chemical messenger in the body called acetylcholine. This chemical helps nerve cells communicate with each other, especially in the brain. By blocking acetylcholine, these drugs can reduce certain symptoms such as muscle spasms, runny nose, or overactive bladder.
However, because acetylcholine is also important for learning and memory, blocking it may affect how the brain processes information.
To better understand how these drugs might influence memory over time, researchers followed a group of 688 older adults for about ten years. The participants were around 74 years old on average when the study began. At the start of the research, none of the participants had any signs of memory loss or problems with thinking.
The research team asked participants whether they had taken anticholinergic medications regularly. In the study, regular use meant taking one of these medications at least once per week for six months or longer. After collecting this information, the scientists tracked the participants’ brain health over time.
Each year, the participants completed tests that measured their memory, attention, and thinking abilities. These tests helped the researchers detect early signs of cognitive decline, which refers to a gradual loss of mental abilities. Cognitive decline can sometimes be an early stage of serious conditions such as Alzheimer’s disease.
The researchers discovered that anticholinergic medication use was quite common among the participants. About one third of the people in the study reported taking these drugs regularly. On average, those who used them were taking about five different medications that had anticholinergic effects.
Some of the medications most often reported in the study included metoprolol, atenolol, loratadine, and bupropion. These medicines are commonly prescribed or used to treat conditions such as high blood pressure, allergies, or depression.
When the researchers compared people who took anticholinergic drugs with those who did not, they found a clear difference in memory health over time. Individuals who used at least one anticholinergic medication had a 47 percent higher risk of developing cognitive impairment compared with those who did not take these drugs.
Cognitive impairment refers to problems with memory, thinking, and decision‑making. These changes can sometimes appear years before a person develops dementia or Alzheimer’s disease. Because of this, identifying factors that increase the risk of cognitive impairment is very important for protecting brain health.
The study also showed that the risk was even higher for people who already had certain biological signs linked to Alzheimer’s disease. Some participants had markers in their body that suggested early Alzheimer’s‑related brain changes. Others carried genetic traits that increased their risk of developing the disease.
For participants who already had Alzheimer’s‑related brain changes, taking anticholinergic drugs increased the risk of cognitive problems dramatically. These individuals were about four times more likely to develop memory issues during the study period.
Participants who carried genes associated with Alzheimer’s disease also faced a higher risk. Among this group, those who used anticholinergic medications were about two and a half times more likely to experience cognitive decline compared with those who did not use the drugs.
These findings suggest that some people may be especially sensitive to the effects of anticholinergic medications on the brain. For individuals who already have risk factors for Alzheimer’s disease, these drugs may accelerate the appearance of memory problems.
The researchers say the results highlight the importance of carefully reviewing medications, especially in older adults who often take several drugs at the same time. Reducing the use of medications with strong anticholinergic effects, when possible, may help protect memory and thinking abilities later in life.
Doctors often have alternative medications that do not affect acetylcholine in the same way. Talking with a healthcare provider about medication choices can help patients find safer options that still manage their symptoms effectively.
In addition to medication choices, lifestyle habits may also play an important role in protecting brain health. Regular exercise, a healthy diet, good sleep, and social activity are all linked to better memory and a lower risk of cognitive decline.
The study was led by Dr. Lisa Delano‑Wood and her research team at the University of California, San Diego. The findings were published in the scientific journal Neurology. The research adds to growing evidence that certain medications may influence long‑term brain health and that careful use of these drugs may help people stay mentally sharp as they age.
If you care about dementia, please read studies about dietary strategies to ward off dementia, and how omega-3 fatty acids fuel your mind.
For more health information, please see recent studies about Choline deficiency linked to Alzheimer’s disease, and what to eat (and avoid) for dementia prevention.
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