At what age can children safely take hydroxyzine (antihistamine)?

Hydroxyzine Age Guidelines for Children

Hydroxyzine can be safely administered to children of all ages, with FDA-approved dosing starting from birth, though specific dosing differs for children under 6 years versus those 6 years and older. 1

FDA-Approved Age-Based Dosing

The FDA label provides clear age stratification for hydroxyzine use in children:

Children Under 6 Years

• Approved dose: 50 mg daily in divided doses for both anxiety/tension management and pruritus (itching) from allergic conditions 1
• This translates to approximately 12.5 mg four times daily or 16.7 mg three times daily

Children 6 Years and Older

• Approved dose: 50-100 mg daily in divided doses for anxiety/tension and allergic pruritus 1
• Higher dosing range reflects increased body weight and metabolic capacity

Premedication/Sedation Dosing

• Weight-based dosing: 0.6 mg/kg of body weight for procedural sedation or premedication 1
• This weight-based approach is appropriate across all pediatric ages 2

Clinical Evidence Supporting Pediatric Use

Pharmacokinetic studies demonstrate hydroxyzine is effective and generally well-tolerated in young children when dosed appropriately:

• A study of 12 children (mean age 6.1 years) with atopic dermatitis found that 0.7 mg/kg three times daily provided optimal pruritus relief with minimal sedation, while higher doses (1.4 mg/kg tid) caused significantly more sedation without additional benefit 3
• Peak serum concentrations occur at approximately 2 hours, with an elimination half-life of 7.1 hours that increases with age 3
• Pruritus suppression exceeded 85% from 2-12 hours post-dose 3

Important Safety Considerations and Caveats

While hydroxyzine has no absolute lower age limit, emerging safety data warrants caution with prolonged use in very young children:

• A large population-based study found that repeated hydroxyzine prescriptions in children under 5 years were associated with increased rates of tics, anxiety disorders, and conduct disturbances by age 10, compared to single prescriptions 4
• The odds ratios for repeat users showed: tic disorders (OR 1.55), anxiety (OR 1.34), and conduct disturbances (OR 1.34) 4
• Recommendation: Use the shortest possible duration in preschool-age children to minimize potential neurodevelopmental risks 4

Documented Adverse Effects

• Sedation is the most common side effect and is dose-dependent 3
• Rare but serious: supraventricular tachycardia has been reported in a 9-year-old on therapeutic doses 5
• Neonatal withdrawal syndrome can occur with maternal use during pregnancy, manifesting as tremors, irritability, hyperactivity, and feeding problems 6

Special Population Adjustments

• Renal impairment: Reduce dose by 50% 2
• Severe hepatic impairment: Avoid use due to sedating effects 2
• Pregnancy: Contraindicated in early pregnancy 2

Practical Administration

• Hydroxyzine is available in syrup formulation, facilitating administration to young children who cannot swallow tablets 2
• Dosing should be adjusted according to individual patient response, but the FDA-approved ranges provide safe starting points 1
• When initiating therapy intramuscularly (e.g., for acute sedation), subsequent doses may be given orally 1