What are the considerations for using hydroxyzine (an antihistamine) in an elderly patient with dementia, experiencing sleep disturbances or agitation?

Hydroxyzine Should Be Avoided in Elderly Patients with Dementia

Hydroxyzine is strongly discouraged for elderly dementia patients experiencing sleep disturbances or agitation due to its anticholinergic properties that worsen confusion and cognitive impairment, lack of evidence for efficacy in this population, and significant safety risks including falls, paradoxical agitation, and QT prolongation. 1, 2

Why Hydroxyzine Is Problematic in Dementia

Anticholinergic Burden Worsens Dementia Symptoms

• The Canadian Consensus Conference on Dementia explicitly recommends minimizing exposure to medications with anticholinergic properties in older persons, and hydroxyzine falls squarely into this category 1
• Anticholinergic medications like hydroxyzine, diphenhydramine, and oxybutynin worsen confusion, agitation, and cognitive function in dementia patients 1, 3
• Over-the-counter antihistamines (including hydroxyzine) have very high rates of side effects, including cognitive impairment, daytime somnolence, and anticholinergic responses 4

Specific Safety Concerns from FDA Labeling

• The FDA warns that sedating drugs may cause confusion and over-sedation in the elderly, and elderly patients generally should be started on low doses and observed closely 2
• Hydroxyzine causes QT prolongation and Torsade de Pointes, particularly dangerous when combined with other QT-prolonging medications commonly used in dementia (citalopram, quetiapine, risperidone) 2
• The drug potentiates central nervous system depressants, increasing risks when combined with other medications this population often receives 2
• Hydroxyzine may cause acute generalized exanthematous pustulosis (AGEP), a serious skin reaction 2

Limited Evidence in Dementia Population

• While one recent study 5 showed hydroxyzine was not inferior to haloperidol for delirium in hospitalized patients, this does not translate to chronic use in dementia patients with behavioral symptoms
• The study population was general hospitalized patients, not specifically elderly dementia patients where anticholinergic burden is particularly problematic 5

What to Use Instead

For Sleep Disturbances in Dementia

Non-pharmacological interventions are the strongly recommended first-line approach:

• Implement bright light therapy during morning hours (09:00-11:00) for 1-2 hours daily at 2,500-5,000 lux, positioned about 1 meter from the patient 1
• Create a sleep-conducive environment by reducing nighttime light and noise, and improve incontinence care to minimize nighttime awakenings 1
• Establish a structured bedtime routine and encourage at least 30 minutes of sunlight exposure daily 1
• Increase physical and social activities during daytime hours, and reduce time spent in bed during the day 1

The American Academy of Sleep Medicine strongly recommends against using sleep-promoting medications in elderly patients with dementia and irregular sleep-wake rhythm disorder due to increased risks of falls, cognitive decline, and other adverse outcomes 1

• Even melatonin has a WEAK AGAINST recommendation due to lack of improvement in total sleep time and potential harm including detrimental effects on mood and daytime functioning 1
• Benzodiazepines should be strictly avoided due to high risk of falls, confusion, and worsening cognitive impairment 1

For Agitation in Dementia

Systematic approach prioritizing non-pharmacological interventions:

Step 1: Identify and Treat Reversible Medical Causes

• Aggressively assess for pain, which is a major contributor to behavioral disturbances in patients who cannot verbally communicate discomfort 3
• Check for urinary tract infections, pneumonia, constipation, urinary retention, and dehydration 1, 3
• Review all medications to identify and discontinue anticholinergic agents (including hydroxyzine) that worsen confusion and agitation 3
• Address sensory impairments (hearing, vision) that increase confusion and fear 3

Step 2: Implement Behavioral Interventions

• Use calm tones, simple one-step commands, and gentle touch for reassurance 1, 3
• Ensure adequate lighting and reduce excessive noise 1, 3
• Provide predictable daily routines and structured activities 1, 3
• Use ABC (antecedent-behavior-consequence) charting to identify specific triggers 3

Step 3: Pharmacological Options (Only After Behavioral Interventions Fail)

For chronic agitation without psychotic features:

• SSRIs are the preferred first-line pharmacological option: citalopram 10 mg/day (maximum 40 mg/day) or sertraline 25-50 mg/day (maximum 200 mg/day) 3, 6, 7
• Assess response within 4 weeks at adequate dosing; if no benefit, taper and discontinue 3
• Trazodone 25 mg/day (maximum 200-400 mg/day) is a second-line option if SSRIs fail, though use caution due to orthostatic hypotension risk 3, 6

For severe agitation with psychotic features or imminent risk of harm:

• Antipsychotics should only be used when the patient is severely agitated, threatening substantial harm to self or others, and behavioral interventions have failed 3, 7
• Risperidone 0.25-0.5 mg at bedtime (maximum 1-2 mg/day) is first-line, with quetiapine 12.5-25 mg twice daily as an alternative 3, 8, 6
• All antipsychotics increase mortality risk 1.6-1.7 times higher than placebo in elderly dementia patients—this must be discussed with the patient's surrogate decision maker before initiation 3, 7
• Use the lowest effective dose for the shortest possible duration, with daily reassessment and attempt to taper within 3-6 months 3, 7

Critical Pitfalls to Avoid

• Never use hydroxyzine or other anticholinergic antihistamines (diphenhydramine, promethazine) in dementia patients 1, 3
• Avoid benzodiazepines except for alcohol or benzodiazepine withdrawal, as they increase delirium incidence and duration and cause paradoxical agitation in approximately 10% of elderly patients 1, 3
• Do not use antipsychotics for mild agitation or behaviors like unfriendliness, poor self-care, repetitive questioning, or wandering—these are unlikely to respond to psychotropics 3
• Never continue psychotropic medications indefinitely without regular reassessment; review need at every visit 3, 7
• Avoid typical antipsychotics (haloperidol, fluphenazine) as first-line therapy due to 50% risk of tardive dyskinesia after 2 years of continuous use in elderly patients 3