Medications That Can Cause or Worsen Sundowning

Quick answer: The drug classes most often linked to worsening sundowning are anticholinergics, benzodiazepines and certain sleep medications. Anticholinergics include common over-the-counter sleep and allergy products containing diphenhydramine — often the 'PM' formulas families buy to help someone sleep, which can sharply increase evening confusion and agitation instead. Polypharmacy multiplies the risk in older adults, whose bodies clear drugs more slowly. Never stop a prescribed medication without speaking to the prescriber first.

Almost every family caring for someone with dementia comes to dread a particular time of day. The afternoon light starts to fade, and with it, calm. Your mother grows restless, anxious, insistent on "going home" though she is already home. Your father, gentle all morning, becomes agitated, suspicious, sometimes angry. This pattern has a name: sundowning. And while it is a common feature of dementia itself, families are often surprised to learn that certain medications can trigger it, or turn a manageable evening into an impossible one.

At DavidStar Home Care, our caregivers see sundowning every day across Broward County, and one of the first questions our coordinators help families raise with their doctor is a simple one: could a medication be making this worse? Surprisingly often, the answer is yes. This guide explains which medications are most commonly involved, why it happens, and what you can safely do, without ever adjusting a prescription on your own.

An important note first: this article is educational, not medical advice. Never start, stop, or change a medication without talking to the prescribing doctor or a pharmacist. Some of these drugs are genuinely necessary, and stopping certain ones abruptly is dangerous.

What sundowning actually is

Sundowning refers to a cluster of symptoms, confusion, agitation, anxiety, pacing, irritability, and sometimes aggression, that emerge or worsen in the late afternoon and evening in people with dementia. The exact cause isn't fully understood, but it's tied to the disruption of the body's internal clock, accumulated fatigue, fading light, and reduced sensory cues as the day winds down. When a medication adds to that burden, the result can be dramatic.

Medication classes most often linked to sundowning

1. Anticholinergic medications

This is the big one. Anticholinergic drugs block acetylcholine, a brain chemical essential for memory and attention, the very chemical already in short supply in Alzheimer's. They are strongly associated with confusion and agitation in older adults. What surprises families most is how many common, even over-the-counter, products are anticholinergic:

• Diphenhydramine (the antihistamine in many allergy products and most over-the-counter "PM" sleep aids)
• Older allergy medications
• Some bladder/overactive-bladder medications
• Certain muscle relaxants
• Some older antidepressants

The over-the-counter nighttime sleep aid is a classic trap: a family gives it hoping to settle a restless evening, and it makes the confusion markedly worse.

2. Benzodiazepines and "Z-drugs"

Medications like lorazepam, diazepam, and alprazolam, along with sleep drugs such as zolpidem, are sometimes prescribed for anxiety or insomnia. In older adults with dementia they can paradoxically increase confusion, agitation, and fall risk, and they're on most expert lists of medications to use with great caution in this population.

3. Steroids

Corticosteroids like prednisone, often prescribed for inflammation, breathing problems, or pain, can cause mood changes, agitation, and insomnia that compound sundowning, particularly at higher doses.

4. Certain sleep, pain, and bladder medications

Some prescription sleep aids, certain opioid pain medications, and several bladder-control drugs (which are often anticholinergic) round out the list of common contributors. Even some medications for nausea fall into this category.

5. Polypharmacy, the cumulative effect

Sometimes no single drug is the villain. Many older adults take five, ten, or more medications, and the combination, especially several mildly anticholinergic drugs stacked together, produces a cumulative "anticholinergic burden" large enough to drive confusion and agitation. Because aging kidneys and livers clear drugs more slowly, levels build up in ways they wouldn't in a younger person.

One of the most powerful things we do for a family isn't a care technique at all. It's helping them get a full medication review. We've seen evenings transform after a doctor removed a single over-the-counter sleep aid. — Chaya Flaxman, Founder, DavidStar Home Care

What to do about it, safely

If you suspect a medication is worsening your loved one's sundowning, here is the safe path:

• Make a complete list of everything they take, including over-the-counter products, supplements, and "as needed" medications. Note the times of day each is taken.
• Request a medication review with the prescribing physician or a pharmacist. Ask specifically about anticholinergic burden and whether any drugs can be reduced, switched, or deprescribed.
• Track the pattern. Keep a simple log of when sundowning is worst and what was taken beforehand. This is genuinely useful clinical information, and it's exactly the kind of observation our caregivers document for families.
• Never stop abruptly. Some of these medications must be tapered. Changes belong to the doctor.

Non-drug strategies that often help more

The best first-line response to sundowning is usually not another pill, it's the environment and routine:

• Maximize bright light during the day and keep evenings well-lit but calm
• Keep a steady daily routine, with activity earlier and a quiet wind-down later
• Limit caffeine, sugar, and naps in the afternoon
• Reduce evening noise, clutter, and stimulation
• Offer reassurance and gentle redirection rather than argument, the approach we cover in our guide on what not to say to someone with dementia

For many Broward County families, the hardest part isn't knowing what to do, it's having the energy to do it calmly, every single evening, on no sleep. That's where professional help changes everything.

When a trained caregiver makes the difference

Sundowning happens at the exact hours when family caregivers are most depleted. A caregiver trained in dementia care can take the evening shift, hold the calm routine consistently, document medication-and-behavior patterns for the doctor, and de-escalate without the frustration that exhaustion breeds. For families facing nighttime confusion and wandering, 24-hour home care ensures someone skilled is present through the night. You can also read our broader guide on how to help someone with dementia.

If your loved one's evenings have become unmanageable, talk to a DavidStar care coordinator for a free, no-pressure conversation, and please, raise the medication question with their doctor. Relief is often closer than families expect.