Can Too Many Medications Cause Reversible Symptoms of Dementia?

Polypharmacy and Drug-Induced Cognitive Impairment

Confused, dazed, and can't remember things? While these symptoms can be caused by Alzheimer's and other types of dementia, there could be another, possibly reversible, cause—medication. Too many medicines, called polypharmacy, can affect your ability to think clearly, remember, and make appropriate decisions.

Different prescription pills in pile
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Drug-Induced Cognitive Impairment

According to one study, cognitive impairment was present in 22% of those taking five or fewer medications, while that rate increased to 33% in people who took more than five medications and 54% in those taking 10 or more medications. American Family Physician reports the risk of developing delirium by taking multiple medicines.

Symptoms of mild cognitive impairment or delirium that develop when a person is taking multiple medications should always be thoroughly investigated.

What Is Polypharmacy?

The word poly means many, and pharmacy refers to medicines. So, polypharmacy is when too many (defined as more than five in some sources and more than six in others) medications are used to treat a person.

There are certainly many situations in which multiple medications are necessary and appropriate, but the use of multiple medications, especially in older adults, also has the potential for unintended negative effects. It contributes to adverse events, hospitalizations, ER visits, and worse.

There are several contributing factors for polypharmacy, including the following:

1. Multiple Healthcare Providers

Often, people will go to more than one practitioner, such as a specialist, for different concerns. If you don't clearly communicate which medicines are being prescribed by the other doctors, or if your medical records are not accurately sent to the next healthcare provider, too many medications might be prescribed.

2. Herbs and Supplements

You should report any herbs or supplements that you're taking to your healthcare provider. Even though they may be completely natural, they can still affect how your body absorbs the medicine and pose the possibility of interaction with medicines.

3. Self-Medicating

Some people feel that if two pills are good, four are better. Or, they borrow medicines from their neighbors for various aches and pains.

Remember that mixing and self-prescribing medications can have negative results, both of not helping the problem you're hoping to address, and of causing harmful drug interactions. A 2018 study reported that out of 170 elderly patients, polypharmacy was diagnosed in 165 patients, equaling 97.1% of participants.

Always talk to your healthcare provider before making any adjustments to your medication regimen.

4. Medicine-Dependent Culture

Particularly in our culture, it's common to look for a medicine for everything. Feeling anxious? Take a pill. Your knee hurts? Have some medicine. High cholesterol? Here's another pill. Of course, there are wonderful medicines available—and they might be the exact remedy you need. But, for some situations, there are other approaches that could be tried first, such as counseling, physical therapy, or a healthier diet and exercise regimen.

5. Medication Administration Errors

For some people, taking medication properly is a challenge. It's not uncommon for people to forget that they took their medication and then take another dose, take it at the wrong time of day, take it with food when it should be without, or get the names of medications confused and take the wrong pill.

Sometimes, a medication administration system can help prevent these types of errors.

6. Over-the-Counter Medicine Usage

There are so many over-the-counter medications available without a prescription, but just like herbs and supplements, you can still take too many of these medicines, and they can also interact negatively with other medicines.

7. Hospitalizations

Sometimes extra medications are prescribed when someone is hospitalized, and they're intended for a temporary condition.

But, as time goes on, those medications may never be discontinued. When you go to a follow-up practitioner's appointment after a hospital stay, ask your healthcare provider to review the medications you're taking to ensure that they're all still appropriate. This process is called medication reconciliation, which is tied to reductions in hospital readmissions. It helps ensure all medications being taken are needed, none are omitted, and all have appropriate indications.

8. Treating Medication Side Effects With Other Medications

This is a very common problem. For example, if a medicine has a side effect of causing constipation, a doctor may prescribe another pill instead of recommending that you exercise more, drink plenty of water and eat lots of fiber.

Based on your condition, that medicine might be exactly what you need to prevent a serious complication like a bowel obstruction. But, it's also possible that for some people, non-drug approaches may resolve the problem just as effectively.

Older Adults and Medication

Care must be taken with prescribing medications for older adults, because their bodies tend to respond more sensitively to medicines. Specifically, older people tend to metabolize, absorb, distribute and excrete drugs more slowly, which is why there's often a different set of guidelines and dosage recommendations for older persons than the general population.


Maintain a personal health record with all of your medications listed, as well as a diagnosis for each medicine. If you don't know why you're taking a medicine, ask your healthcare provider. When you go to a healthcare provider, bring your record with you. Templates of these records are available online.

Medical practitioners are encouraged to "start low and go slow" with medications, as well as to pay attention to medicines that are on the Beers list, a compilation of drugs that can be potentially inappropriate for older adults.

A Word From Verywell

While medications can be very helpful and appropriate to treat certain conditions, remember that each mediation potentially has side effects the can interact with other medicines. Being aware that too many medications can create confusion and memory problems may help you identify this concern in yourself or someone you love. Don't hesitate to ask your healthcare provider about each medicine you're taking so that you both are clear on why they're necessary for your health and well-being.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. Agbabiaka TB, Spencer NH, Khanom S, Goodman C. Prevalence of drug–herb and drug–supplement interactions in older adults: a cross-sectional survey. British Journal of General Practice. 2018;68(675):e711-e717. doi. 10.3399/bjgp18X699101. Published October, 2018.

  3. de Oliveira SBV, Barroso SCC, Bicalho MAC, Reis AMM. Profile of drugs used for self-medication by elderly attended at a referral center. Einstein (Sao Paulo). 2018;16(4):eAO4372. doi. 10.31744/einstein_journal/2018AO4372, Published November, 2018.

  4. O’Mahony D, Gallagher P, Lavan A. Methods to reduce prescribing errors in elderly patients with multimorbidity. CIA. Published online June 2016:857. doi. 10.2147/CIA.S80280. Published June, 2016.

  5. Qato DM, Wilder J, Schumm LP, Gillet V, Alexander GC. Changes in prescription and over-the-counter medication and dietary supplement use among older adults in the united states, 2005 vs 2011. JAMA Internal Medicine. 2016;176(4):473. doi. 10.1001/jamainternmed.2015.8581. Published April, 2016.

  6. Chang TI, Park H, Kim DW, et al. Polypharmacy, hospitalization, and mortality risk: a nationwide cohort study. Scientific Reports. 2020;10(1):18964. doi. 10.1038/s41598-020-75888-8. Published November, 2020.

Additional Reading

By Esther Heerema, MSW
Esther Heerema, MSW, shares practical tips gained from working with hundreds of people whose lives are touched by Alzheimer's disease and other kinds of dementia.