In 40 seconds
Sundowning is the late-afternoon and early-evening worsening of agitation, confusion, restlessness and wandering common in moderate Alzheimer's and Lewy body dementia. It affects around 20% of people with dementia at some point. There is no completed PEMF or rTMS RCT specifically for sundowning. The first-line non-pharmacological interventions with the strongest evidence are bright light therapy (especially morning or late-afternoon timed exposure to alter circadian phase), structured daytime activity to prevent daytime napping, and melatonin where appropriate. The 2023 systematic review of TMS for behavioural and psychological symptoms of dementia (BPSD) found a positive direction-of-effect signal for rTMS that remains preliminary. Wu 2015 (n=54) showed DLPFC rTMS reduced BEHAVE-AD scores in moderate AD. None of this is targeted at sundowning specifically.
Quick facts
- Sundowning prevalence: ~20% of people with dementia at some point
- PEMF RCT in sundowning: None completed
- rTMS RCT in sundowning: None specifically — BPSD signal in broader trials
- First-line non-pharm: Bright light therapy, structured activity, sleep hygiene
- Melatonin: May help in dementia sleep where appropriate — review with GP
- Wu 2015: n=54 — DLPFC rTMS reduced BEHAVE-AD scores
- 2023 BPSD review: Positive direction-of-effect signal, preliminary
What actually helps sundowning
Sundowning has a circadian-disruption signature: late-afternoon cortisol misalignment, daytime fragmentation of sleep, and reduced exposure to bright outdoor light. The most evidence-supported interventions target these directly.
Bright light therapy
Morning bright light (10,000 lux for 30 minutes) has the strongest evidence for re-anchoring circadian phase. In care-home settings, ambient bright-light protocols and timed exposure during the late afternoon can reduce agitation and improve sleep consolidation. The Cochrane reviews of light therapy in dementia have been cautious about quality of evidence but consistent on direction of effect.
Structured daytime activity
Daytime napping and inactivity fragments night-time sleep and worsens late-afternoon agitation. Group activity programmes, outdoor walking, and physical engagement during the morning and early afternoon reduce sundowning in observational studies and small trials.
Melatonin
Melatonin (modified-release where prescribed) has acceptable evidence for sleep consolidation in some dementia phenotypes. It does not directly treat sundowning agitation but reducing nocturnal awakenings can break the daytime-napping cycle that feeds sundowning. Discuss with the GP — modified-release melatonin is licensed in adults with insomnia.
Where rTMS sits
The 2023 systematic review of TMS for behavioural and psychological symptoms of dementia found a positive direction-of-effect signal for reducing agitation, apathy and depression. The Wu 2015 trial (n=54, moderate AD) showed DLPFC rTMS reduced BEHAVE-AD scores at 6 weeks with persistence to 3 months. No trial has targeted sundowning specifically as a primary endpoint. The evidence is suggestive, not confirmatory, and not sufficient for any UK clinic to claim rTMS treats sundowning.
Where PEMF sits
There is no completed PEMF RCT specifically for sundowning. General PEMF sleep trials exist but most are small and brand-funded. Do not extrapolate general PEMF sleep evidence to a person with dementia — the comorbidities, medication interactions and capacity-to-consent issues are different.
What to ask the GP
For a relative whose sundowning is disrupting the household, a structured GP review should cover: medication review (anticholinergics worsen sundowning; review polypharmacy), pain assessment (untreated pain commonly drives late-afternoon agitation), urinary tract infection screen (common precipitant of acute behavioural change), referral to a memory clinic for a structured non-pharmacological plan, and consideration of bright light therapy. PEMF is not on this first-line list.
The legitimate carer use
Sundowning is exhausting for carers. PEMF has acceptable evidence for the carer's own sleep and stress. A carer using a PEMF mat for their own back pain or insomnia is a reasonable wellness choice — frame it correctly when discussing it.
Frequently asked questions
Can a PEMF mat in the bedroom reduce my mum's sundowning?
There is no published trial showing a PEMF mat reduces sundowning. The first-line interventions with the strongest evidence are bright light therapy, structured daytime activity and (where appropriate) melatonin. Discuss with the GP.
Is light therapy on the NHS?
Bright light therapy is recommended in NICE dementia guidance where appropriate. Lamps are widely available privately; NHS provision varies by trust and is usually via the memory clinic or community mental-health team.
Does melatonin actually help sundowning?
Melatonin does not treat sundowning agitation directly but improves sleep consolidation in some dementia phenotypes, which can break the daytime-napping cycle. Modified-release melatonin is licensed in adults. Discuss with the GP.
What about clinical rTMS for the agitation that comes with sundowning?
The 2023 BPSD systematic review of TMS shows a positive direction-of-effect signal that remains preliminary. Wu 2015 showed reduced BEHAVE-AD scores. No trial has targeted sundowning as a primary endpoint. NICE NG97 still recommends rTMS only inside a clinical trial.
Which medications make sundowning worse?
Anticholinergic medications (some bladder medications, some antihistamines, tricyclic antidepressants) commonly worsen confusion and sundowning. A polypharmacy review is high-yield. Ask the GP or pharmacist for an anticholinergic burden review.
My dad seems in more pain in the late afternoon — could that be driving it?
Yes. Untreated pain is a common but under-recognised driver of late-afternoon agitation. Structured pain assessment (Abbey Pain Scale or DOLOPLUS in non-verbal patients) and a trial of regular paracetamol can sometimes dramatically reduce sundowning.
Does PEMF help my own sleep as a carer?
PEMF has acceptable evidence for general sleep quality and stress. As a carer, this is wellness use — a reasonable adjunct alongside ordinary sleep hygiene.
Should we move my mum into a care home if sundowning is bad?
Persistent sundowning that is disrupting the household and unsafe is a common trigger for considering more structured care. The decision should be made in consultation with the memory clinic and social services, not driven by exhaustion alone. Respite care or day-centre attendance is often an interim step worth trying first.
Related dementia pages on PEMF UK
Looking for a PEMF clinic in the UK?
We list every credible PEMF therapy provider in the UK. Please remember: no UK clinic can legally claim to treat dementia with PEMF or rTMS.