What are the recommended hydroxyzine dosing regimens for anxiety, sedation, and pruritus in adults, children (≥6 months), and in elderly or hepatic‑impaired patients?

Hydroxyzine Dosing Recommendations

Hydroxyzine dosing varies by indication: for anxiety in adults use 50-100 mg four times daily; for pruritus in adults use 25 mg three to four times daily; for children under 6 years use 50 mg daily in divided doses; and for children over 6 years use 50-100 mg daily in divided doses, with dose reductions required in elderly patients and those with moderate renal impairment. 1

Adult Dosing by Indication

Anxiety and Tension

• Standard dose: 50-100 mg four times daily for symptomatic relief of anxiety and tension associated with psychoneurosis or as adjunct in organic disease states 1
• Dosing range of 10-50 mg per dose is also supported for anxiety management, though hydroxyzine is not considered first-line due to limited high-quality evidence 2

Pruritus (Allergic Conditions, Urticaria, Dermatoses)

• Standard dose: 25 mg three to four times daily for management of pruritus due to allergic conditions such as chronic urticaria, atopic and contact dermatoses, and histamine-mediated pruritus 1
• Alternative dosing of 10-50 mg, often given at night, is recommended when combining with non-sedating antihistamines during the day for patients with urticaria who have sleep disturbances 2

Preoperative Sedation

• 50-100 mg when used as premedication and following general anesthesia 1

Pediatric Dosing

Children Under 6 Years

• 50 mg daily in divided doses for both anxiety/tension and pruritus indications 1

Children Over 6 Years

• 50-100 mg daily in divided doses for both anxiety/tension and pruritus indications 1

Evidence-Based Pediatric Considerations

• A pharmacokinetic study demonstrated that 0.7 mg/kg three times daily was as effective as 1.4 mg/kg three times daily in relieving pruritus in children with atopic dermatitis, with significantly less sedation at the lower dose 3
• The lower dose (0.7 mg/kg tid) provided greater than 85% pruritus suppression from 2 to 12 hours after administration 3
• Hydroxyzine is approved for anxiolytic use in children in both Europe and the United States, available in tablets and syrup with few contraindications 4

Preoperative Sedation in Children

• 0.6 mg/kg of body weight when used as premedication 1

Special Population Adjustments

Elderly Patients

• Start with lower doses and monitor closely, as elderly patients are more sensitive to psychomotor impairment and at increased risk for falls, fractures, and anticholinergic effects 2
• Dose should be reduced in elderly patients 2
• Sedative antihistamines like hydroxyzine should not be prescribed for pruritus in elderly skin due to safety concerns 4

Renal Impairment

• Moderate renal impairment: Reduce dose by half 2
• Severe renal impairment: Avoid hydroxyzine 2

Hepatic Impairment

• Avoid in severe liver disease because the sedating effect is inappropriate 2

Pregnancy

• Contraindicated during early pregnancy 2

Critical Safety Considerations

Sedation and Performance Impairment

• Significant sedative effects can impair driving ability, work performance, and cognitive function 2
• Drivers in fatal accidents are 1.5 times more likely to be taking first-generation antihistamines like hydroxyzine 2
• Performance impairment can occur without subjective awareness of drowsiness, and impaired driving worsens with concurrent activities like cell phone use 2
• Second-generation antihistamines are generally preferred over hydroxyzine for daytime use due to reduced sedative effects 2

Combination Therapy Strategy

• For patients with urticaria and sleep disturbances, consider combining a non-sedating antihistamine (e.g., loratadine 10 mg) during the day with hydroxyzine 10-50 mg at bedtime 2
• This AM/PM dosing regimen may still result in daytime drowsiness due to hydroxyzine's prolonged half-life (mean 7.1 hours in children, increasing with age) 3, 2

Dosing Titration Principles

• Adjust dosage according to the patient's response to therapy, as with all potent medications 1
• When treatment is initiated by intramuscular route, subsequent doses may be administered orally 1
• Real-world data demonstrates significant improvement in pruritus symptoms and quality of life over 12 weeks, with 48% of patients achieving symptom relief leading to early termination 5

Common Pitfalls to Avoid

• Do not use hydroxyzine as first-line for anxiety when non-sedating alternatives are available, particularly in patients who drive or operate machinery 2
• Do not prescribe to elderly patients with pruritus due to fall risk and anticholinergic burden 4
• Do not combine with other anxiolytics, particularly benzodiazepines, as combinations are contraindicated 4
• Do not overlook renal function before prescribing, as dose adjustment is mandatory in moderate impairment and the drug should be avoided in severe impairment 2