Alert: 8 Types of Medications That May Affect Memory and Brain Health
Many people take medication every day to manage allergies, pain, sleep problems, depression, or other health conditions. These medicines can be helpful and sometimes essential. However, certain medications may also cause side effects that affect memory, concentration, alertness, or thinking—particularly in older adults.
Research has also found an association between long-term use of some medications and an increased risk of dementia. But there is an important distinction: an association does not prove that a medicine directly causes dementia or permanently damages the brain.
Understanding the possible risks can help you have a more informed conversation with your doctor or pharmacist about the medicines you take.
1. Certain Antihistamines Used for Allergies
Some older antihistamines have anticholinergic effects, meaning they block the action of acetylcholine, a chemical messenger involved in memory and other brain functions.
Examples include diphenhydramine, commonly sold as Benadryl in the United States, and chlorpheniramine.
These medicines may cause:
Drowsiness and reduced alertness.
Confusion, particularly in older adults.
Difficulty concentrating.
Short-term memory problems.
Some observational studies have linked long-term exposure to strong anticholinergic medicines with a higher risk of dementia. However, researchers have not established that these medicines directly cause dementia in every person who takes them.
What to do: Ask a pharmacist whether a less sedating or less anticholinergic alternative may be appropriate for your allergies. Do not assume that every allergy medicine carries the same risks.
2. Certain Sleep Medications
Sleep medications can help some people with short-term or persistent sleep difficulties, but some can affect the central nervous system.
Examples include benzodiazepines and certain prescription sleep medicines, such as zolpidem.
Possible side effects include:
Drowsiness the following day.
Problems with balance and coordination.
Confusion or memory gaps.
Increased risk of falls, especially in older adults.
Some studies have examined whether long-term use of these medicines is associated with dementia. The findings are mixed, and factors such as the underlying sleep disorder and early symptoms of dementia may complicate the results.
What to do: If you use a sleep medication regularly, discuss its benefits, risks, and duration of use with your prescriber. Do not abruptly stop benzodiazepines, as sudden withdrawal can be dangerous.
3. Benzodiazepines Used for Anxiety
Benzodiazepines are prescribed for conditions such as anxiety and certain seizure disorders. Examples include diazepam, lorazepam, and alprazolam.
These medicines slow activity in the central nervous system. Depending on the medicine, dose, and individual, they may cause:
Drowsiness.
Slower reactions.
Reduced concentration.
Difficulty forming new memories.
Confusion, particularly in vulnerable older adults.
Long-term use deserves careful review, especially in older adults or people who take several medications that cause sedation.
Although some observational studies have investigated a possible connection between benzodiazepines and dementia, the evidence does not establish that these drugs directly cause dementia.
What to do: Ask your healthcare professional to review whether continued treatment is necessary and whether other approaches may help. Never suddenly discontinue regular benzodiazepine use without medical supervision.
4. Certain Bladder-Control Medications
Some medicines used to treat an overactive bladder work by blocking acetylcholine. This can reduce bladder contractions but may also affect other parts of the body.
Examples include oxybutynin and tolterodine.
Potential side effects include:
Dry mouth.
Constipation.
Blurred vision.
Drowsiness or confusion.
Problems with memory or attention in some people.
The potential effect on cognition is particularly important for older adults who already take several medicines with anticholinergic properties.
Researchers have investigated associations between long-term use of certain bladder anticholinergics and dementia risk. The evidence varies by medicine and does not mean that everyone who takes these drugs will develop memory problems.
What to do: Ask your prescriber whether your current treatment remains the best option for you. Do not stop bladder medication without discussing the possible consequences and alternatives.
5. Some Antidepressants
Antidepressants are used to treat depression, anxiety, and other conditions. Their effects on memory and alertness depend on the particular medicine and the person taking it.
Certain older antidepressants, including amitriptyline, have strong anticholinergic effects and may cause confusion, drowsiness, or difficulty concentrating.
Other antidepressants have different side-effect profiles and should not automatically be considered equally risky.
It is also important to remember that depression itself can affect sleep, attention, concentration, and memory. Untreated depression can therefore complicate the assessment of cognitive symptoms.
What to do: If you notice new memory problems after starting an antidepressant or changing the dose, speak with your prescriber. Do not discontinue antidepressants abruptly without professional guidance.
6. Opioid Pain Medications
Opioids are prescribed for certain types of moderate to severe pain. Examples include morphine, oxycodone, and hydrocodone.
These medicines can cause:
Sleepiness and slowed reactions.
Dizziness.
Confusion or delirium, especially in older adults.
Breathing problems when taken in excessive amounts or combined with certain sedatives.
The risk of confusion may increase during acute illness, after a dose change, or when several sedating medicines are used together.
These effects are not the same as proving that opioids cause dementia. However, medication-related confusion should be taken seriously, particularly when it begins suddenly.
What to do: Take opioids only as prescribed and discuss persistent drowsiness or confusion with your healthcare professional. Severe sleepiness or slow, difficult breathing may be a medical emergency.
7. Certain Antipsychotic Medications
Antipsychotic medicines are used for conditions such as schizophrenia and bipolar disorder. In some circumstances, they may also be prescribed for severe behavioral or psychological symptoms.
Examples include risperidone, quetiapine, and olanzapine.
Depending on the medicine, side effects may include:
Drowsiness.
Dizziness.
Reduced alertness.
Movement-related symptoms.
Confusion in some patients.
These medicines require particular caution in older adults with dementia because antipsychotics can increase the risk of serious adverse outcomes in this population.
However, they are not all used for the same reasons, and their risks must be considered alongside the potential benefits for an individual's condition.
What to do: Anyone taking an antipsychotic should have regular medication reviews. Never stop treatment suddenly without speaking with the prescribing clinician.
8. Muscle Relaxants and Other Sedating Medicines
Some muscle relaxants, including cyclobenzaprine, can cause drowsiness and impair alertness. Other medicines with sedating effects may contribute to similar problems.
The risk can be greater when these medicines are combined with alcohol, opioids, sleep medications, or other drugs that slow the central nervous system.
Possible effects include:
Dizziness.
Reduced coordination.
Difficulty concentrating.
Confusion.
Increased risk of falls.
These effects may be temporary, but they can be particularly dangerous for older adults who are already at risk of falling.
What to do: Ask your pharmacist to check for interactions among all your medicines, including nonprescription products and supplements. Avoid alcohol when your medication instructions warn against combining the two.
Who May Be More Vulnerable to Medication-Related Memory Problems?
Some people are more likely than others to experience cognitive side effects.
Risk may be higher in people who:
Are older adults, particularly those who are frail.
Take multiple medications with sedating or anticholinergic effects.
Have existing memory or thinking difficulties.
Have kidney or liver problems that affect how medicines are processed.
Have recently started a medicine or changed a dose.
Are experiencing dehydration, infection, or another acute illness.
Taking several medicines with anticholinergic effects can increase a person's overall anticholinergic burden. This is one reason why a complete medication review can be valuable.
Can Medication-Related Confusion Be Reversed?
Sometimes, yes. Certain medicines can cause temporary confusion, drowsiness, or memory difficulties that improve when the dose is adjusted or the medicine is changed under medical supervision.
However, the outcome depends on the cause, the medication involved, and the individual's health.
New memory problems should not automatically be blamed on medication. Other possible causes include infections, sleep disorders, depression, vitamin deficiencies, thyroid problems, and neurological conditions.
Sudden confusion requires urgent medical assessment, particularly if it develops over hours or days. If confusion occurs with facial drooping, weakness on one side, difficulty speaking, or a sudden severe headache, seek emergency care.
How to Protect Your Brain While Taking Medication
You do not necessarily need to avoid these medicines. Many provide important benefits when used appropriately. The goal is to make sure that every medicine remains necessary and that its benefits outweigh its risks.
Consider these practical steps:
Keep an updated medication list. Include prescription medicines, over-the-counter products, vitamins, and supplements.
Schedule medication reviews. Ask your doctor or pharmacist whether any medicines could be contributing to memory problems, drowsiness, or falls.
Ask about alternatives. Depending on your condition, a medicine with fewer sedating or anticholinergic effects may be suitable.
Follow the prescribed dose. Never take extra doses or combine medicines without checking whether it is safe.
Report new symptoms. Tell your healthcare professional if you notice unusual confusion, memory difficulties, or excessive sleepiness.
Never stop medication on your own. Some medicines can cause serious withdrawal symptoms or a return of the condition they treat if stopped abruptly.
Frequently Asked Questions
Do these eight types of medication definitely cause dementia?
No. Some can cause confusion or memory problems, and some have been associated with increased dementia risk in observational research. This does not prove that the medicines directly cause dementia, and the level of evidence varies among drug classes.
Should older adults stop taking antihistamines, sleeping pills, or antidepressants?
Not automatically. The safest approach is to review the specific medicine, dose, duration of use, medical history, and available alternatives with a healthcare professional.
Can taking several medications affect memory?
Yes. Some medicines can interact or have additive sedating or anticholinergic effects. A clinician or pharmacist can review the full medication list and identify potentially avoidable risks.
What if I have already taken one of these medicines for years?
Do not panic. Taking one of these medicines does not mean that you will develop dementia. If you have concerns, arrange a medication review rather than stopping treatment yourself.
What is the difference between confusion and dementia?
Confusion can develop suddenly and may result from medication effects, infection, dehydration, or other urgent conditions. Dementia generally involves a persistent decline in cognitive abilities that affects daily life. A healthcare professional can assess the symptoms and determine the cause.
Final Thoughts
Some commonly used medicines can affect memory, alertness, and thinking, especially in older adults. Certain medications—particularly those with strong anticholinergic effects—have also been associated with dementia risk in some studies, although a direct cause-and-effect relationship has not been established for every medicine.
The best response is not fear or abruptly stopping treatment. It is making informed decisions with a qualified healthcare professional, reviewing medicines regularly, and investigating new cognitive symptoms.
Protecting brain health begins with asking questions, understanding possible side effects, and making sure your treatment plan is right for you.
What do you think? Let us know in the comments! 💬❤️
Medical disclaimer: This article is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Never change or stop prescribed medication without consulting your healthcare professional.
References
National Institute on Aging: Research on anticholinergic medicines and dementia risk.
National Institute for Health and Care Excellence (NICE): Guidance on medicines that may contribute to cognitive impairment.
Cochrane: Review of anticholinergic medicines and future memory and thinking problems.
