Medications That Cause Sundowning: What Families Should Know
Which medications can make sundowning worse?
Families often notice that confusion, restlessness, agitation, or sleep problems become worse later in the day. Medication is not always the cause, but certain medicines can contribute to confusion, sedation, delirium, or changes in sleep that make sundowning symptoms more noticeable.
Can medications cause sundowning?
Some medications can make sundowning symptoms worse, but they are not necessarily the direct cause of sundowning. Medicines that increase confusion, sedation, agitation, sleep disruption, or delirium may make late-day behavioral changes more noticeable in an older adult living with dementia.
Medication groups that deserve review include anticholinergic medicines, first-generation antihistamines and sleep aids, benzodiazepines, Z-drugs, antipsychotics, opioids, systemic corticosteroids, and certain H2-receptor blockers.
The safest next step is a complete medication review with the person's physician, prescribing clinician, or pharmacist. Include prescription medicines, over-the-counter products, vitamins, supplements, allergy medicines, sleep products, and as-needed medications.
Tell the clinician if symptoms changed after a medication was started, stopped, increased, decreased, or moved to another time of day.
Sudden confusion can be different from a recurring evening pattern.
Sundowning usually describes a pattern that appears or becomes more noticeable in the late afternoon or evening. A sudden, dramatic, or rapidly fluctuating change in thinking or behavior may be delirium or another medical problem instead.
Medication effects, medication withdrawal, infection, dehydration, pain, constipation, electrolyte problems, illness, and other medical issues can contribute to sudden confusion. A new change from the person's usual mental status should be discussed promptly with a health care professional.
What does sundowning mean?
Sundowning is a pattern of increased confusion or behavioral changes that may occur from late afternoon into the evening or night in a person living with Alzheimer's disease or another form of dementia.
Families may notice pacing, anxiety, agitation, irritability, disorientation, difficulty settling down, disrupted sleep, hallucinations, resistance to care, or greater confusion as daylight fades.
There is no single cause. Fatigue, disrupted sleep, changes in the body's internal clock, low lighting, unfamiliar surroundings, pain, stress, illness, and medication effects may all contribute.
Medications that may worsen sundowning-like symptoms
The phrase "medications that cause sundowning" is commonly searched, but medication effects are more complicated. A drug may increase confusion, sedation, delirium, agitation, or sleep problems. In someone who already has dementia-related evening changes, those effects can make sundowning appear worse.
| Medication group | Examples families may recognize | Why it may deserve review |
|---|---|---|
| Anticholinergic medications | Diphenhydramine, doxylamine, hydroxyzine, meclizine, promethazine, and other medicines with significant anticholinergic effects. | Anticholinergic medicines can contribute to confusion and delirium in older adults. The combined effect can become more important when several anticholinergic medicines are taken together. |
| First-generation antihistamines and sleep aids | Diphenhydramine and doxylamine are common ingredients in some allergy medicines, nighttime products, and over-the-counter sleep aids. | These medicines can have strong anticholinergic and sedating effects in older adults. |
| Benzodiazepines | Lorazepam, alprazolam, clonazepam, diazepam, and related medications. | Older adults are more sensitive to these medicines. The AGS Beers Criteria notes increased risk of cognitive impairment, delirium, falls, and fractures. |
| Z-drug sleep medications | Zolpidem, eszopiclone, and zaleplon. | These sleep medicines can have adverse effects similar to benzodiazepines in older adults, including delirium and falls. |
| Antipsychotics | This medication class may sometimes be prescribed for severe behavioral or psychiatric symptoms. | Antipsychotic use in dementia requires careful clinical judgment because of significant risks. Families should discuss the reason for use, dose, risks, benefits, and ongoing need with the prescribing clinician. |
| Opioids | Prescription opioid pain medicines. | Opioids can contribute to sedation and may increase delirium risk in susceptible older adults. Untreated pain can also worsen behavior, so medication changes should be clinically guided. |
| Systemic corticosteroids | Oral or injectable corticosteroid treatment. | The AGS Beers Criteria lists systemic corticosteroids among medicines that may worsen delirium in older adults who are at risk. |
| H2-receptor blockers | Cimetidine, famotidine, and nizatidine. | These medicines are included in the AGS Beers Criteria list of medications to use cautiously in older adults with or at high risk of delirium. |
Can Benadryl make dementia confusion worse?
Diphenhydramine, the active ingredient in many Benadryl products, has strong anticholinergic properties. The AGS Beers Criteria identifies oral diphenhydramine as a medicine generally best avoided in older adults in routine situations because of anticholinergic effects and the risk of confusion.
MedlinePlus also advises that diphenhydramine generally should not be used routinely in adults age 65 and older, except in certain circumstances such as serious allergic reactions, because other medications may be safer or more effective.
Families sometimes overlook over-the-counter allergy, cold, nighttime, and "PM" medicines during a medication review. Bring these products to the attention of the physician or pharmacist along with prescription medications.
Why medication effects can look worse later in the day
Medication effects do not happen in isolation. An older adult may already be tired, overstimulated, uncomfortable, hungry, dehydrated, in pain, or struggling with a disrupted sleep-wake cycle by late afternoon.
A sedating or cognitively impairing medication may add to those existing factors. Timing can also matter. A dose taken later in the day, an as-needed medicine, or several central nervous system medications used together may change alertness or behavior.
That does not mean families should change medication timing on their own. A physician or pharmacist should review whether the medicine, dose, interaction, or timing may be contributing.
What should families bring to a medication review?
A complete list is more useful than a list of prescriptions alone. Include anything the person takes regularly or occasionally.
One useful question to ask the care team is: "Could any prescription medicine, over-the-counter product, supplement, dose, interaction, or medication timing be contributing to this new evening confusion?"
Keep a simple record of what is changing
Families often remember that an evening was difficult but not exactly when the behavior changed or what happened beforehand. A short daily record can give the clinician more useful information.
When should families contact a health care professional?
Contact the person's health care professional promptly when confusion is new, suddenly worse, or significantly different from the person's normal pattern.
If the situation appears to be an emergency or the person is in immediate danger, seek emergency medical care.
Do not stop medications without clinical guidance
Finding out that a medication may contribute to confusion does not mean it should be stopped suddenly. Some medications can cause withdrawal, rebound symptoms, uncontrolled pain, seizures, or other complications when discontinued incorrectly.
The prescribing clinician or pharmacist can review why the medicine is being used, whether the dose remains appropriate, possible interactions, other treatment options, and whether a change should happen gradually.
How home care can support a family managing sundowning
Home care does not replace medical evaluation or medication management by the person's physician or pharmacist. It can help families create more consistency around daily routines and notice meaningful changes that should be reported to the care team.
Consistent routines
Regular meal, hygiene, activity, rest, and bedtime routines may reduce unnecessary disruption later in the day.
Observation
Caregivers may help families notice changes in alertness, sleep, eating, hydration, mobility, behavior, and daily function.
Care-plan support
Appropriate caregivers can support authorized routines and services according to the person's care plan and professional scope.
Family caregiver relief
Respite care can give family caregivers time to rest while their loved one continues receiving appropriate assistance at home.
Skilled nursing
When clinically appropriate, an RN or LPN may support nursing needs that require licensed care under the applicable plan of care.
Communication
Changes in behavior or function can be documented and shared with the appropriate family member or clinical team when needed.
Learn more about senior home care in Florida , in-home respite care , or Private Duty Nursing for adults .
Families comparing longer care schedules can also review the cost of 24/7 in-home care .
Medications and sundowning FAQs
What medications can cause sundowning?
There is not one established list of medications that directly causes sundowning. Medicines that increase confusion, sedation, agitation, sleep disruption, or delirium may worsen sundowning-like symptoms. Medication groups that deserve review include anticholinergics, first-generation antihistamines, benzodiazepines, Z-drug sleep medications, antipsychotics, opioids, systemic corticosteroids, and certain H2 blockers.
Can Benadryl make sundowning worse?
Diphenhydramine, the active ingredient in many Benadryl products, has strong anticholinergic effects and may contribute to confusion in older adults. Families caring for someone with dementia should discuss its use with the person's physician or pharmacist.
Can sleeping pills make dementia confusion worse?
Some sleep medications can increase confusion, sedation, falls, or delirium in older adults. Benzodiazepines and Z-drugs such as zolpidem, eszopiclone, and zaleplon deserve careful review in older adults with cognitive impairment.
Can benzodiazepines worsen confusion in an older adult?
Yes. The AGS Beers Criteria notes that benzodiazepines increase the risk of cognitive impairment and delirium in older adults. They should not be stopped suddenly without guidance from the prescribing clinician.
Can opioids cause confusion in older adults?
Opioids may contribute to sedation and delirium in susceptible older adults. Pain itself can also contribute to behavioral changes, so treatment decisions should be made with the prescribing clinician rather than by stopping pain medication without guidance.
Should I stop a medication if sundowning gets worse?
Do not stop a prescribed medication without speaking with the prescribing clinician or pharmacist. Some medicines can cause withdrawal, rebound symptoms, seizures, uncontrolled pain, or other problems when stopped incorrectly.
How can I tell sundowning from delirium?
Sundowning usually follows a recurring late-afternoon or evening pattern. Delirium is typically a sudden or rapidly changing state of confusion. A new or dramatic change from the person's usual mental status should be evaluated by a health care professional.
When should I call the doctor about worsening confusion?
Contact the person's health care professional promptly if confusion begins suddenly, becomes substantially worse than usual, follows a medication change, or occurs with unusual sleepiness, a fall, infection symptoms, dehydration, pain, or another significant health change.
Medical sources
- Alzheimer's Association: Sleep Issues and Sundowning
- Alzheimer's Association: Treatments for Behavior
- American Geriatrics Society: 2023 Updated AGS Beers Criteria
- MedlinePlus: Diphenhydramine Drug Information
- MedlinePlus: Delirium
- HealthInAging.org: Delirium Care and Treatment
This article is for general educational purposes and does not replace medical evaluation, diagnosis, medication review, or treatment advice from a physician, pharmacist, or other qualified health care professional. Do not start, stop, or change a medication based only on this article.
Dolores Fishbein, MSN, RN
Pediatric PDN, Complex Care, Medicaid & Family Education
Dolores Fishbein, MSN, RN, contributes to and reviews Dynamiks Home Care educational resources related to nursing, complex care, home health care, Medicaid, and family education. Her work helps families understand care options, recognize questions worth bringing to the clinical team, and prepare for conversations about care at home.
This article discusses medication-related risks and behavior changes for educational purposes. Medication decisions should be made with the person's prescribing clinician or pharmacist.
Does your family need more support caring for an older adult at home?
Dynamiks Home Care can help families explore senior home care, respite care, home health aide services, and skilled nursing based on the person's needs, location, care plan, payer requirements, authorization, and staffing availability.
