Medicines That May Cause Dementia-Like Symptoms and How to Manage Them

David S. Klein, MD FACA FACPM
Oct 7
4 min read

Not all memory loss or confusion comes from Alzheimer’s or other true dementias. Sometimes, the medicines we take can cause very similar symptoms—like forgetfulness, slowed thinking, or trouble finding words. The good news is that these side effects often improve once the medicine is stopped or changed. Never stop a medication on your own—always talk with me first.

1. Anticholinergic Drugs

These medicines block a brain chemical called acetylcholine, which is important for memory. They include:

Older allergy medicines like diphenhydramine (Benadryl, many “PM” sleep aids).
Bladder medicines like oxybutynin.
Some older antidepressants and stomach medicines.

Why it matters: People who take these drugs for years have a higher chance of developing dementia. Even short-term, they can cause brain fog and confusion.

2. Anxiety and Sleep Pills

This group includes benzodiazepines (like lorazepam, alprazolam, diazepam) and “Z-drugs” (zolpidem/Ambien).

Why it matters: They can cause drowsiness, memory problems, and confusion, especially in older adults. Using them for a long time may raise dementia risk.

3. Antipsychotics

Medicines used for severe mood or behavior problems (like risperidone, haloperidol, quetiapine).

Why it matters: They can increase confusion and even raise the risk of death in older adults with dementia. They should be used only when absolutely necessary.

4. Strong Pain Pills (Opioids)

Examples: oxycodone, morphine, hydrocodone.

Why it matters: They can make thinking slow, cause confusion, and trigger delirium. This is more common at higher doses.

5. Seizure and Nerve Pain Medicines

Topiramate is well known for causing word-finding problems and mental “slowness.” Gabapentin and pregabalin can also make people groggy or forgetful.

6. Steroids

Prednisone and other “cortisone” medicines can affect mood and memory. Some people feel hyper and can’t sleep, while others may feel depressed or confused.

7. Other Medicines to Watch

Certain stomach drugs (like ranitidine and cimetidine) can sometimes cause confusion in older adults.
Some antibiotics (like ciprofloxacin and levofloxacin) have FDA warnings about confusion and memory changes.

What You Can Do

Bring all your medicines (including over-the-counter ones) to your doctor visits.
Ask about your “anticholinergic burden.” This is the total effect of all memory-blocking drugs you take.
Never stop a drug suddenly without medical advice. Some need to be tapered off slowly.
Ask about safer options. Many times, there are alternatives with fewer brain effects.
Report new confusion or memory changes right away.

Key Message

Not all memory problems mean you have dementia. Sometimes the cause is the medicines themselves—and that means we can often fix it. By reviewing your medication list together, we can lower your risk, protect your brain, and help you feel clearer.

Some medicines are better than others in preventing confusion, memory loss or dizziness:

1. Benedryl is a problem. Better to use Claritin, if you are over 60 years of age.

2. Prilosec is a problem. Better to use Famotidine.

3. Oxybutinin, Ditropan. Better to use myrbetriq.

4. Statins like atorvastatin and lovastatin. Better to use Rosuvastatin.

References

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