What are the indications and dosing guidelines for hydroxyzine in adults and children with anxiety disorders?

Hydroxyzine Indications and Dosing

Hydroxyzine is FDA-approved for symptomatic relief of anxiety and tension associated with psychoneurosis, as an adjunct in organic disease states manifesting anxiety, and for pruritus management, though it is notably absent from major anxiety disorder treatment guidelines as a recommended first-line agent. 1, 2

FDA-Approved Indications

Anxiety and Tension

• Adults: 50-100 mg four times daily for symptomatic relief of anxiety and tension associated with psychoneurosis and as adjunct therapy in organic disease states where anxiety is present 1
• Children under 6 years: 50 mg daily in divided doses 1
• Children over 6 years: 50-100 mg daily in divided doses 1

Pruritus Management

• Adults: 25 mg three to four times daily for allergic conditions including chronic urticaria, atopic and contact dermatoses, and histamine-mediated pruritus 1
• Children under 6 years: 50 mg daily in divided doses 1
• Children over 6 years: 50-100 mg daily in divided doses 1

Procedural Sedation

• Adults: 50-100 mg as premedication and following general anesthesia 1
• Children: 0.6 mg/kg body weight 1
• When initiated intramuscularly, subsequent doses may be administered orally 1

Critical Clinical Context

Position in Anxiety Treatment Guidelines

Hydroxyzine is conspicuously absent from all major contemporary anxiety disorder treatment guidelines, including NICE, S3, Canadian CPG, and the 2020 AACAP guidelines. 2 The American Academy of Child and Adolescent Psychiatry firmly establishes SSRIs and SNRIs as first-line treatments for generalized anxiety disorder based on robust evidence 3, 2. CBT is considered first-line treatment for anxiety in children and adolescents, particularly for mild to moderate presentations, with SSRI medication as an alternative, especially for more severe presentations 3.

Limited Evidence Base

While older research from the 1990s demonstrated hydroxyzine superiority over placebo in GAD (50 mg/day showing significant anxiolytic effect from week one) 4, 5, a 2010 Cochrane systematic review concluded that due to high risk of bias in included studies, small sample sizes, and limited number of trials, hydroxyzine cannot be recommended as a reliable first-line treatment in GAD 6. More recent prehospital research (2021) found that adding hydroxyzine to morphine for acute pain management did not reduce pain or anxiety, indicating it is not beneficial in this context 7.

Appropriate Clinical Scenarios

Procedural Anxiolysis in Pediatrics

Hydroxyzine is approved and practical for anxiolysis during medical procedures in pediatric populations 2. This represents a legitimate niche indication where its sedative properties are advantageous.

Psychiatric Emergency Settings

Hydroxyzine can be used as chemical restraint in psychiatric settings for children and adolescents 2, though JCAHO standards prohibit using hydroxyzine as PRN chemical restraint 2. This is a critical pitfall to avoid.

Safety Considerations and Contraindications

Absolute Contraindications

• Early pregnancy: Contraindicated per UK manufacturer guidelines 3, 2
• Severe liver disease: Should be avoided due to inappropriate sedating effects 3, 2

Adverse Effect Profile

• Sedation/drowsiness: Most common side effect (28% vs 14% with placebo), typically appearing during the first week and progressively diminishing 5, 3, 2
• Weight gain (12% vs 10% placebo) 5
• Dry mouth (14% vs 5% placebo) 5
• Loss of concentration (9% vs 8% placebo) 5
• Insomnia (9% vs 6% placebo) 5

The sedation profile may significantly impair daytime function 3, 2, making it less suitable for patients requiring alertness for work, school, or driving.

Drug Interactions

Hydroxyzine should be used with caution when combined with other CNS depressants due to additive sedative effects 3.

Clinical Algorithm for Hydroxyzine Use

For anxiety disorders in adults and children:

1. First-line: Offer SSRIs (fluoxetine, sertraline, fluvoxamine, paroxetine, escitalopram) or CBT 3
2. Second-line: Consider SNRIs (venlafaxine) 3
3. Combination therapy: CBT plus SSRI for moderate-to-severe presentations 3
4. Hydroxyzine: Reserve for short-term symptomatic relief only when first-line treatments are unavailable, contraindicated, or as adjunctive therapy in organic disease states with anxiety 1, 6

For pruritus:

• Hydroxyzine represents a reasonable option at 25 mg three to four times daily in adults 1, 3

For procedural anxiolysis:

• Appropriate in pediatric populations at 0.6 mg/kg 2, 1

Key Pitfalls to Avoid

• Do not position hydroxyzine as first-line anxiety treatment when evidence-based options (SSRIs, SNRIs, CBT) are available 3, 2
• Do not use as PRN chemical restraint in psychiatric settings due to JCAHO prohibition 2
• Do not prescribe in early pregnancy 3, 2
• Do not use in severe liver disease 3, 2
• Warn patients about sedation affecting daily activities, particularly during the first week 5, 3
• Adjust dosing according to patient response rather than using fixed dosing 1