Medicines that can worsen memory

Some everyday medicines can make thinking foggy, especially after age 65. A pill bought at the drugstore for allergies or sleep can do this. So can a prescription for an overactive bladder or for anxiety. In a person who already has memory problems, these medicines can make confusion, falls and agitation worse.

The good news is that this is one of the few causes of worse memory that you can often do something about. This page explains which medicines matter most, what experts recommend, and how to get every pill in the house checked.

Why older brains react more to some medicines

As we age, the liver and kidneys clear many drugs more slowly. Medicines stay in the body longer and build up. The aging brain also becomes more sensitive to drugs that cause sleepiness.

Dementia adds to this. Alzheimer's disease lowers the brain's supply of acetylcholine, a chemical messenger that helps with memory and attention. Medicines that block acetylcholine take away even more. That is why the same pill that is fine for a 40-year-old can leave a person with dementia confused or unsteady.

There is also a tug-of-war to know about. Memory medicines like donepezil, rivastigmine and galantamine work by raising acetylcholine. Anticholinergic drugs push the other way. Taking both can mean each one works less well.

What the Beers Criteria say

The American Geriatrics Society (AGS) Beers Criteria is a list of medicines that are often a poor choice for adults 65 and older. The AGS has kept it up to date since 2011 and revises it every few years. This page uses the 2023 update.¹

The list has five parts:⁵

• Medicines most older adults should avoid
• Medicines to avoid with certain health problems, such as dementia
• Medicines to use with caution
• Drug combinations that can cause harm together
• Medicines to avoid or adjust when the kidneys are weak

For people with dementia or memory problems, the 2023 list says to avoid four groups: anticholinergic drugs, benzodiazepines, Z-drug sleeping pills and antipsychotics.¹ The list also warns against combining anticholinergic drugs. It also warns against taking three or more drugs that act on the brain together, because this raises the risk of falls.¹

Anticholinergic medicines: the biggest group

Anticholinergic drugs block acetylcholine. Besides confusion, they can cause dry mouth, constipation, blurry vision, trouble passing urine and a fast heartbeat. Many people do not know their medicine is in this group.

Benadryl and "PM" products. Diphenhydramine is in many drugstore sleep aids and nighttime pain relievers. The National Library of Medicine says older adults generally should not use it, except for a serious allergic reaction.⁶ For people with Lewy body dementia, these "PM" products can also cause agitation.⁷

Bladder pills. Urinary urgency and leaking are common in dementia. Older bladder pills like oxybutynin are strongly anticholinergic. The 2024 urology guideline tells doctors to talk with patients about the possible risk of memory problems and dementia when they prescribe these drugs.⁸ The same guideline offers another drug group (beta-3 agonists) and bladder training as options.⁸ See bladder and bowel problems for non-drug help.

Do these medicines cause dementia?

This is still being studied. Two large studies point in the same direction:

• In a U.S. study of about 3,400 people age 65 and older, those with the most anticholinergic use had about a 54% higher risk of dementia. "The most" meant about three years or more of daily use.⁹
• In an English study of about 284,000 people, high use of certain anticholinergic drugs was linked with about 1.5 times the odds of dementia. The link was clearest for bladder pills, antidepressants, Parkinson's drugs, antipsychotics and seizure drugs.¹⁰

Both studies were observational. That means they show a link, not proof that the drugs cause dementia.^9,10 Even so, experts say it makes sense to use these drugs less when safer choices exist.^9,10

Benzodiazepines and Z-drug sleeping pills

Benzodiazepines are calming and sleep medicines. Common ones include alprazolam (Xanax), lorazepam (Ativan), clonazepam (Klonopin), diazepam (Valium) and temazepam (Restoril).⁴ Z-drugs are newer sleeping pills: zolpidem (Ambien), eszopiclone (Lunesta) and zaleplon (Sonata).²

In older adults, both groups can cause:

• Next-day grogginess and slower thinking, even when you feel awake²
• Confusion and memory gaps¹
• Falls and broken bones¹
• Car crashes¹

The FDA has a boxed warning (its strongest warning) on all benzodiazepines. It covers misuse, addiction, physical dependence and withdrawal.⁴ Taking them with opioid pain medicines can slow breathing to a dangerous level.⁴ Z-drugs carry their own boxed warning. They can cause sleepwalking, sleep-driving and other actions done while not fully awake. Some of these events have led to serious injury or death.²

For people with Lewy body dementia, the Lewy Body Dementia Association says benzodiazepines are best avoided unless there is a specific reason. One exception doctors sometimes make is clonazepam at night for acting out dreams.⁷

For safer ways to help sleep in dementia, see sleep medicines in dementia and sleep problems in dementia.

Other medicines worth a second look

These are not always wrong, but they deserve a careful review in a person with memory problems:

• Antipsychotics (such as haloperidol, risperidone and quetiapine). The Beers list says to avoid them for behavior in dementia unless non-drug steps have failed and the person is a danger to self or others.¹ People with Lewy body dementia can have severe reactions, including much stiffer movement.⁷ Read more on medicines for agitation and behavior.
• Opioid pain medicines. They can cause sleepiness and confusion, and they can trigger delirium.¹¹ Pain still needs treatment, so ask about the safest plan.
• Several brain-acting drugs at once. In a Medicare study of 1.2 million people with dementia, about 1 in 7 took three or more brain-acting drugs (such as sedatives, antidepressants, antipsychotics or opioids) for more than a month.¹²
• Alcohol. It adds to the effects of sleep and anxiety medicines. See alcohol-related brain damage.

Sudden confusion: when to get help fast

Delirium is a sudden change in thinking and attention. It can come on over hours or days. Medicines are a common cause, including sedatives, opioids and withdrawal from a medicine that was stopped.¹¹ People with dementia are at higher risk.¹¹ Delirium is often treatable, so it should never be brushed off as "just the dementia getting worse."¹¹

Learn more on treatable conditions that look like dementia and hospital stays and emergency rooms.

The brown-bag medicine review

A brown-bag review is simple. You put every medicine the person takes into a bag and bring it to the doctor or pharmacist. Seeing the real bottles shows what is actually being taken, and how. It can catch mistakes and medicines the doctor did not know about.³

1. Gather everything. Include prescriptions, drugstore medicines, vitamins, supplements and herbal products. Also bring creams, eye drops, inhalers, patches and liquids.³
2. Bring pills as they are. Bring the original bottles, plus any weekly pill box you use.³
3. Check the nightstand and bathroom. Sleep aids and "PM" products are easy to forget.
4. Bring a written list of all medicines and supplements to every visit, too.⁵
5. Ask the key questions (see below).
6. Make one plan. Write down any changes and who will follow up. Update the list.

Questions to ask

Could any of these medicines affect memory, sleepiness or balance?

Ask the doctor or pharmacist to check the whole list against the Beers Criteria. Ask if there is a safer or more effective choice.⁵

Is each medicine still needed?

Some medicines were started years ago for a problem that is gone. Stopping or lowering medicines that no longer help is called deprescribing. It should match the person's health goals.¹²

If we change something, how should we do it?

Ask whether a medicine needs a slow taper, what side effects to watch for, and when to check back. Do not stop a medicine without checking with the doctor first.^4,5

What can we try instead of a pill?

For sleep, bladder urgency and worry, there are often non-drug steps that help. Bladder training is one example.⁸

Tips for caregivers

• Use one pharmacy if you can, so the pharmacist sees the full picture.
• Read labels on drugstore products. Look for diphenhydramine or the letters "PM" in sleep and cold products.⁶
• Watch after any change. Note new confusion, sleepiness, falls or bladder problems in a behavior diary.
• Plan for hospital stays. Bring the medicine list. Ask the team to avoid sleeping pills and anticholinergic drugs when possible.
• Keep a review on the calendar. A brown-bag check at least once a year, and after every hospital stay, is a good habit.

For daily systems like pill organizers and locked storage, see managing medicines at home. For an overview of memory medicines, go back to dementia medicines. For falls, see preventing falls.

Education only. This page is general information written from the sources listed. It is not medical, legal or financial advice and does not replace a doctor, therapist or lawyer who knows your situation. How we write and check pages.