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hydroxyzine

Adjunctive therapy

Brands: VISTARIL, ATARAX

Published 2025-12-21 · Last reviewed 2025-12-28 · 5 references

Content sourced from FDA labeling (DailyMed) and peer-reviewed literature.

Print sheet Review evidence

At a glance

Class: Adjunctive therapy·Typical dose: Anxiety/acute distress (off label patterns vary): 25–50 mg every 6–8 hours as needed; consider 10–25 mg starting doses in older adults or high fall risk.·PK (metabolism / half-life): Hepatic metabolism; clinical duration can outlast perceived half-life due to sedation and anticholinergic effects.·LAI available: No

Class: Adjunctive therapy
Typical dose: Anxiety/acute distress (off label patterns vary): 25–50 mg every 6–8 hours as needed; consider 10–25 mg starting doses in older adults or high fall risk.
PK (metabolism / half-life): Hepatic metabolism; clinical duration can outlast perceived half-life due to sedation and anticholinergic effects.
LAI available: No

Quick answers

What is hydroxyzine?: Hydroxyzine (brands Vistaril/Atarax) is a first-generation antihistamine used for anxiety symptoms, pruritus, and procedural sedation. In psychiatry it is commonly used as a short-term, “as needed” calming agent when clinicians want to avoid benzodiazepines.
What is VISTARIL?: VISTARIL is a brand name for hydroxyzine (other brands: ATARAX).
What is VISTARIL (hydroxyzine) used for?: Label indications include: Anxiety symptoms (label); pruritus; pre/postoperative sedation (label varies by product).
What drug class is VISTARIL (hydroxyzine)?: Antihistamine.
What is the mechanism of action of VISTARIL (hydroxyzine)?: First-generation antihistamine (H1 antagonist) with sedating and anxiolytic effects; anticholinergic/antiemetic properties.
What strengths does VISTARIL (hydroxyzine) come in?: Oral tablets (hydroxyzine HCl) and oral capsules (hydroxyzine pamoate) are commonly used; strengths vary by manufacturer.
What is hydroxyzine hydrochloride (HCl)?: Two oral salt forms are used clinically (hydroxyzine hydrochloride and hydroxyzine pamoate). Both are sedating and can impair driving and increase fall risk.

General information

Hydroxyzine is a first-generation antihistamine used for anxiety symptoms, pruritus, and sedation. In psychiatric practice it is often used short-term as a PRN calming agent when clinicians want to avoid benzodiazepines.

Two oral salt forms are used clinically (hydroxyzine hydrochloride and hydroxyzine pamoate). Both are sedating and carry anticholinergic and fall-risk liabilities, especially in older adults.

Because it is anticholinergic and sedating, hydroxyzine can worsen confusion, constipation, and urinary retention—especially in older adults; QT risk also limits use and makes medication reconciliation and electrolyte assessment important.

Hydroxyzine is often used as a short-term PRN bridge rather than a chronic daily medication; if anxiety symptoms are frequent, plans often shift toward primary therapy (psychotherapy, SSRIs/SNRIs) rather than escalating PRN sedatives.

The hydroxyzine compare view, the hydroxyzine evidence feed, and the hydroxyzine print page can support side-by-side review and counseling when aligning short-term calming strategies with longer-term anxiety and sleep plans.

U.S. approvals

Anxiety symptoms (label varies by product)
Pruritus (label varies by product)

Formulations & strengths

Oral tablets (hydroxyzine HCl) and oral capsules (hydroxyzine pamoate) are commonly used; strengths vary by manufacturer.

Generic availability

Generic formulations widely available.

QT risk and anticholinergic burden are key limiters; hydroxyzine is generally treated as a time-limited adjunct while primary anxiety therapies take effect. It is widely available and often refilled “by momentum,” so a documented stop plan and reassessment within days to weeks are common when doses are being used frequently.

View labelExact

Mechanism of action

Refer to the Glossary entry on Neurotransmitters for background on receptor systems involved in serious mental illness.

H1 receptor antagonism reduces allergic symptoms and produces sedation.

Anticholinergic and antiemetic properties contribute to calming and nausea relief.

H1 antagonism (sedation).
Anticholinergic activity (dry mouth, constipation, urinary retention).

Metabolism & pharmacokinetics

Hepatic metabolism; clinical duration can outlast perceived half-life due to sedation and anticholinergic effects.
Caution is warranted in older adults and those with impaired clearance; lower starting doses and reassessment of next-day impairment are common.
Sedation can persist beyond the perceived dosing window; driving safety and daytime functioning are often reassessed after initiation or dose increases.

Dosing & administration

Anxiety/acute distress (off label patterns vary): 25–50 mg every 6–8 hours as needed; consider 10–25 mg starting doses in older adults or high fall risk.
Insomnia symptoms (off label): 25–50 mg at bedtime as needed; nightly indefinite use is generally avoided.
Combining with other sedatives can increase impairment; follow-up within days to weeks helps prevent automatic refills.
If daytime use is considered, counseling about driving impairment and lowest-effective dosing is common; many patients do better with bedtime-only use.

Monitoring & labs

Sedation, falls, and driving impairment are often reassessed after initiation and during dose changes—especially in older adults.
Anticholinergic effects (constipation, urinary retention, confusion) are commonly monitored; total anticholinergic burden is minimized when possible.
QT risk: QT-prolonging co-medications and electrolytes are typically reviewed, and baseline ECGs are often considered when risk factors stack.
If use becomes frequent, the diagnosis is often revisited and plans may shift toward long-term anxiety treatment rather than continued PRN escalation.

Sources: FDA/DailyMed labels; EMA QT communication; guideline statements.

Adverse effects

FDA boxed warnings

Common side effects (≥10%)

Sedation / impaired coordination: Counseling often covers driving, machinery, and falls; effects can persist into the next day.
Dry mouth / constipation: Anticholinergic effects; consider bowel regimens and hydration.
Dizziness: Higher risk in older adults; orthostasis and fall risk are often monitored.
Blurred vision / urinary retention: Use is generally avoided in patients with significant BPH or narrow-angle glaucoma when possible.

Other notable effects

QT prolongation/torsades risk—generally avoided in known prolonged QT; risk is lower when QT-risk stacking is minimized.
Rare serious skin reactions (AGEP) and hypersensitivity; label warns about cross-sensitivity with cetirizine/levocetirizine.
Delirium and urinary retention are more likely in older adults and in patients with high anticholinergic burden; consider alternatives when these risks are present.

Interactions

Additive CNS depression with alcohol, opioids, benzodiazepines, and sedating antipsychotics.
Additive QT risk with other QT-prolonging agents; ECG monitoring is often considered when risk factors stack.
Additive anticholinergic burden with low-potency antipsychotics and bladder antimuscarinics increases delirium risk.
Stacking QT-risk agents (certain antipsychotics, methadone, antiarrhythmics) increases risk; minimizing combinations is preferred when feasible. When combinations occur, ECG monitoring and electrolyte correction are commonly considered.

Other useful information

CBT-based approaches for insomnia and psychotherapy/SSRI/SNRI strategies for persistent anxiety are typically emphasized, with hydroxyzine used as a short-term bridge.
Frequent reassessment and a documented stop plan help prevent refill momentum; chronic daily use in older adults is generally avoided when possible.
If QT risk factors exist (cardiac disease, electrolyte issues, multiple QT meds), baseline ECGs are often considered and alternatives may be preferred when feasible.
Short prescriptions with planned follow-up and a documented stop plan can reduce automatic refills; when anxiety remains frequent, the focus often shifts to primary therapy rather than escalating PRN sedatives.

References

Related hubs:SMI toolkit·Support resources