What medications are used to manage sundowning in patients with dementia?

Medication Management for Sundowning in Dementia

Non-pharmacologic interventions should be the first-line approach for sundowning, but when medications are necessary, low-dose atypical antipsychotics (particularly risperidone 0.5-1 mg), cholinesterase inhibitors, or melatonin are the primary options, with light therapy as an important adjunct. 1

Initial Management Strategy

Non-Pharmacologic Interventions (First-Line)

Before considering any medication, implement these evidence-based strategies:

• Environmental modifications: Use lighting to reduce confusion and restlessness at night, avoid glare from windows and mirrors, reduce noise from television, and minimize household clutter 1
• Structured routines: Provide predictable daily schedules with routine exercise, meals, and bedtime at consistent times 1
• Daytime activity: Restrict daytime sleep and implement mild activity schedules to improve nighttime sleep 2
• Bright light therapy: Expose patients to bright lights during daytime hours, which may help regulate circadian rhythms 3, 2

The American Geriatrics Society emphasizes that non-pharmacological interventions should be exhausted before considering medications for behavioral symptoms in dementia 4

Pharmacologic Options When Non-Pharmacologic Measures Fail

Cholinesterase Inhibitors (Preferred Initial Pharmacologic Approach)

Cholinesterase inhibitors may improve behavioral symptoms including sundowning and should be considered as first-line pharmacologic therapy:

• Donepezil, rivastigmine, or galantamine are FDA-approved for Alzheimer's disease and may reduce agitation and behavioral disturbances 1, 4, 3
• These agents address the underlying disease process while potentially ameliorating sundowning symptoms 3
• Rivastigmine dosing: Start 1.5 mg twice daily, increase by 1.5 mg twice daily every 4 weeks as tolerated to maximum 6 mg twice daily; take with food to reduce gastrointestinal side effects 1
• Galantamine dosing: Start 4 mg twice daily with meals for 4 weeks, then increase to 8 mg twice daily 1

Atypical Antipsychotics (For Severe Behavioral Disturbances)

When behavioral symptoms persist despite cholinesterase inhibitor therapy and pose significant risk, low-dose atypical antipsychotics may be necessary:

• Risperidone is the most studied agent for sundowning specifically, with evidence showing efficacy for long-term treatment of late afternoon/evening agitation 5, 6
• Dosing: Start 0.5 mg once daily at bedtime for 3 days, then increase to 1 mg divided twice daily (morning and evening); mean effective dose is typically 1 mg/day 6
• Risperidone demonstrates significant reductions in agitation, aggression, irritability, delusions, sleep disorders, and anxiety with relatively low rates of extrapyramidal symptoms in elderly patients 5, 6

Critical caveat: The FDA has issued a black box warning regarding increased risk of death when antipsychotics are used for dementia-related behavioral disturbances 1. Use only when patients pose serious risk of harm to themselves or others, and only for short-term duration 1, 4

Melatonin

Melatonin may be considered given the circadian rhythm disturbances underlying sundowning:

• The neurophysiology of sundowning involves degeneration of the suprachiasmatic nucleus and decreased melatonin production 3
• However, guidelines suggest avoiding melatonin as treatment for irregular sleep-wake rhythm disorder in older people with dementia (weak recommendation against) 1
• This creates a clinical dilemma, as the theoretical rationale is strong but guideline evidence is limited 3
• If used, dosing typically starts at 3 mg and may increase by 3-mg increments to 15 mg 1

Antidepressants (For Comorbid Depression)

If depression accompanies sundowning symptoms:

• Selective serotonin reuptake inhibitors such as citalopram or sertraline are preferred due to minimal anticholinergic effects 1, 4
• These agents are effective for depression superimposed on Alzheimer's disease and have favorable side effect profiles 1

Medications to AVOID

Sleep-Promoting Medications (Strong Recommendation Against)

Do NOT use benzodiazepines or other hypnotics for sundowning in elderly patients with dementia:

• The American Academy of Sleep Medicine makes a strong recommendation against sleep-promoting medications for irregular sleep-wake rhythm disorder in demented elderly patients 1
• These medications increase risks of falls, cognitive impairment, and other adverse outcomes 1
• Benzodiazepines (including clonazepam, lorazepam, diazepam) and benzodiazepine-like agents (zolpidem, zaleplon) worsen cognitive function, cause sedation, impair mobility leading to injurious falls, and have habituation/withdrawal risks 1

Anticholinergic Medications

Avoid medications with anticholinergic properties as they cause CNS impairment, delirium, slowed comprehension, and worsen cognitive function in dementia 1

Treatment Algorithm

1. Optimize comorbid conditions (pain, infection, constipation, urinary retention) that may trigger behavioral symptoms 1
2. Implement comprehensive non-pharmacologic interventions including environmental modifications, structured routines, and bright light therapy 1, 2
3. If pharmacologic therapy becomes necessary, initiate a cholinesterase inhibitor if not already prescribed 1, 3
4. For persistent severe agitation/aggression despite above measures, add low-dose risperidone (0.5-1 mg/day) with careful monitoring 5, 6
5. Start low, go slow: Use geriatric dosing principles, monitor for side effects, and attempt dose reduction after 4-6 months of behavioral control 1
6. Reassess regularly and taper psychotropic agents periodically to determine if continued therapy is required 1

Common Pitfalls to Avoid

• Do not reach for benzodiazepines despite their sedating properties—they worsen outcomes in elderly patients with dementia 1
• Avoid polypharmacy: Address one target symptom at a time rather than adding multiple agents simultaneously 1
• Do not use antipsychotics as first-line therapy without attempting non-pharmacologic interventions and cholinesterase inhibitors first 1, 4
• Monitor for anticholinergic burden from cumulative medication effects, which can paradoxically worsen confusion and agitation 1