Autism and Sundowning: How to Manage Evening Struggles.

Lately we’ve been having a tremendous amount of trouble “managing” K at night. I don’t like to use that word, but don’t know what else to call it. It’s been taking both of us to get through the evening and it’s been very tiring if one of us is at basketball with B.

In a nutshell, he’s very active and nothing pleases him. The behavior is like part sensory-seeking, but sometimes it also looks like it could be the beginning of an anxiety attack. The usual preferred items, de-escalating techniques and so on no longer work. Please note, I’m not a doctor nor do I play one on the internet. I am sharing experiences so that you can pursue this with your child’s medical team.

Like many other families like mine, I keep a secret stash of highly preferred items that he has very limited access to and none of them work. His food, meds, schedule–nothing has changed. This usually starts right after dinner and at some point he just wears himself out and either falls asleep on the floor or puts himself to bed.

It makes evenings very stressful as he paces and races around the house, continually putting himself in unsafe situations. That’s why if only one of us is home, it’s fatiguing. You literally get nothing done and by the time it’s all over, I’m too tired to do anything. The other day, outta nowhere, it occurred to me: Is he sundowning? Is sundowning and autism a thing? So I asked on my Facebook page–does your family experience this? I’m sharing those answers below.

What is Sundowning?

Sundowning, also known as “sundown syndrome,” is a pattern of increased confusion, agitation, anxiety, or restlessness that typically begins in the late afternoon or early evening. It most often affects people with Alzheimer’s disease or other forms of dementia, though it can occasionally appear in individuals with other neurological conditions.

Sundowning is a recognized pattern in older adults with Alzheimer’s or other forms of dementia, but many parents and caregivers of autistic children do report seeing similar behaviors: increased agitation, meltdowns, or dysregulation in the late afternoon or early evening.

What Sundowning Looks Like

You might notice that someone is relatively calm or oriented during the day, but then—like a switch—things change once the sun starts to set. The sun setting thing, hence the term sundowning, is a hallmark. However, for us, it’s happening in the summer, and the entire episode is usually over before the sun sets. It does happen with us later in the day.

They may:

• Pace or wander
• Become more irritable or paranoid
• Ask repetitive questions
• Have trouble sleeping
• Yell or lash out
• Try to leave the house or remove clothing inappropriately

What Causes Sundowning

Why It Happens

There’s no single cause, but several factors may contribute:

• Circadian rhythm disruption (their body’s internal clock is off)
• Fatigue or overstimulation from the day’s events
• Low lighting or shadows in the evening that increase confusion or fear
• Unmet needs like hunger, pain, or needing the bathroom—harder for them to express clearly
• Medication side effects that become more pronounced later in the day

“Sundowning” isn’t formally part of the autism diagnostic criteria, it is something that comes up in real life. And it’s worth paying attention to.

Are Autism and Sundowning Being Studied?

Sundowning is a term rooted in dementia research. It describes a pattern of increased confusion, agitation, or restlessness that begins in the late afternoon or early evening, especially among people with Alzheimer’s or other dementias.

As for autism, there’s no formal acknowledgment or extensive clinical research specifically calling evening meltdowns “sundowning.” But many families and professionals notice that autistic individuals, particularly children, do show similar late-day dysregulation. I found that part interesting (Mayo clinic website) because my son is an adult, but many of the respondents on my Facebook page said it’s happening with younger kids.

Why It Happens in Autism

Think of it this way: by the time a child (or adult) with autism gets to the end of the day, their nervous system may be running on empty. They’ve had to:

• Mask or suppress behaviors all day (someone suggested this to me on Facebook, but K does not mask)
• Navigate sensory overload (school bells, cafeteria noise, itchy clothes, bright lights)
• Manage transitions, social interactions, and changes in routine

That’s a lot of energy spent. So by 4 or 5 PM, their ability to cope may drop off a cliff.

You might see:

• Meltdowns or shutdowns
• Increased stimming or vocalizations
• Resistance to transitions (like dinner, bath, bedtime)
• Repetitive questions or scripting
• Emotional outbursts that feel “out of the blue” but are really a buildup

What to Do About It

Even if it’s not technically called sundowning, the strategies are very similar:

• Keep routines tight. Predictability lowers stress.
• Build in a sensory “cool-down” right after school or activities (swing, quiet time, headphones, etc.)
• Lower expectations in the evening. This is not the time for new demands, complex conversations, or “just one more thing.”
• Watch for triggers like hunger, thirst, fatigue, or overstimulation from screens.
• Use visuals or timers to prep for transitions like bath or bed.

Also, if this is a pattern and it’s happening regularly, bring it up in your IEP or behavior planning. A Functional Behavior Assessment (FBA) might help identify what’s really going on, and you can ask for support with after-school regulation or transitions. I have another article about after-school meltdowns, also known as ‘after school restraint collapse.’ Talk to both your child’s medical team and IEP team to see how these incidents are related, and what can be put in place.

What This All Means

• There’s no formal research explicitly calling it “autism sundowning.”
• But behavioral overlaps are real—late-day meltdowns or shutdowns do happen, and they may be tied to:
  • Cumulative sensory overload
  • Fatigue and daily buildup of stress
  • Underlying sleep issues or circadian disruption
• Essentially, while the word “sundowning” isn’t used in academic autism research, the observed patterns and scientific clues clearly converge.

I expect that we will be hearing more about this in the next decade or so.

Families Experiencing Sundowning

If you are experiencing this, know that you’re not alone. When I asked about it on Facebook, here is a sample of the replies.

1. “We are struggling with that too. It doesn’t help that I’m also losing my own ability to regulate at that time of day.” ~LB
2. “I’ve been asking that question! I’m a caregiver for someone with intellectual and physical needs. He’s in his late 50s and his diagnosis is what you’d expect from 40-50yrs ago, broad and non specific. I notice alot of traits I feel are more autism related. Anyway, certain times of the day, the last year or 2 he gets very agitated angry sad, hitting but before that he has always been so happy all the time, very sweet and easy to redirect. To me it looks like sundowning or dementia related. Its just so far out of his normal character to be mean or angry.” ~TM
3. “I’ve been wondering about this for a few years, too, as we have an uptick in challenging behaviors (to include eloping) as it nears sunset. I really haven’t found much info on it, but some parents hint at it in needing medication changed to dinnertime instead of bedtime. I’m very interested to hear what others have to say.” ~CO
4. “We learned about this unfortunately this past winter. My son needs to leave the house between 4-7pm. We’ve seen an uptick this year.  We’ve tried to move med schedules but it still happens. I panick every day around this time because I or my husband needs to be available to get in the car. Otherwise we see elopement or worse.” ~MM
5. “My son who is profoundly autistic and intellectually disabled starts becoming aggressive around that time. He tries to beat/hit/slap/etc our family dog. We are trying to teach him to breathe through it but it has been hard.” ~HA
6. “Solidarity. We are walking on egg shells around here every evening.” ~NS
7. “I have noticed this too, and am relieved to know I’m not the only one.” ~SS
8. “Yes, it’s a thing. There’s something in the neurological wiring.” ~SE
9. “I’m level 1 but between 7-10pm I get restless and agitated for no reason. Can’t get comfortable, get panicky for no reason, just a weird burst of energy that doesn’t make sense. It’s been worse the last few weeks. Eventually I will fall asleep but sometimes it goes on forever. So aggravating. I wonder if that’s a thing I need to get checked out or it’s just the tism out of wack because of the season changes.” ~MR
10. “Omg….i been wondering why the heck my son gets this way in the early evening! He’s on the moderate part of the spectrum and does this MANY evenings….including this very moment lol” ~RG
11. “My 8 year old has been going through this for years. Its awful.” ~AZ
12. “Living this right nowwww” ~BN

For each family, you’re going to have to look at your situation–is it a shutdown or meltdown? Is it a medication issue? Burnout from masking all day? Sensory overload? Who knows.

I just know I need it fixed because it’s been a few months for us that this happens several nights a week, and our next neuro appointment isn’t until October.

Bottom line: It may or may not technically be “sundowning” in the dementia sense, but yes, many autistic people do experience late-day dysregulation, and it’s real.