What is the recommended dosage of Hydroxyzine (Vistaril) for a 13-year-old?

Hydroxyzine Dosage for a 13-Year-Old

For a 13-year-old, hydroxyzine should be dosed at 50-100 mg daily in divided doses, as this age falls into the "children over 6 years" category per FDA labeling. 1

Specific Dosing by Indication

For Anxiety and Tension

• 50-100 mg daily in divided doses for children over 6 years 1
• This can be administered as 12.5-25 mg three to four times daily, depending on symptom severity and tolerability

For Pruritus (Itching from Allergic Conditions)

• 50-100 mg daily in divided doses for children over 6 years 1
• A well-studied regimen in pediatric atopic dermatitis is 0.7 mg/kg three times daily, which provides effective antipruritic relief with minimal sedation 2
• For a typical 13-year-old weighing approximately 45-50 kg, this translates to roughly 30-35 mg three times daily

For Premedication/Sedation

• 0.6 mg/kg of body weight when used as premedication or following general anesthesia 1
• For a 50 kg adolescent, this would be approximately 30 mg

Pharmacokinetic Considerations in Adolescents

• Peak serum concentrations occur at approximately 2 hours after oral administration 2
• Elimination half-life in children averages 7.1 hours and increases with age 2
• Antipruritic effects last 1-24 hours, with peak suppression occurring 2-12 hours post-dose 2

Practical Dosing Strategy

Start with the lower end of the dosing range (50 mg daily) and titrate upward based on response:

• Begin with 12.5-25 mg twice or three times daily 1
• Assess response after 3-5 days
• If inadequate symptom control, increase to 25 mg three to four times daily (75-100 mg total daily dose) 1
• Adjust dosing according to the patient's response to therapy 1

Critical Safety Warnings

Cardiovascular Concerns

• Monitor for palpitations, chest tightness, or tachycardia, as supraventricular tachycardia has been reported in a 9-year-old on clinical doses 3
• Discontinue immediately if cardiac symptoms develop 3

Central Nervous System Effects

• Sedation is the most common adverse effect and typically diminishes with continued use 4, 2
• Hydroxyzine can cause fatigue, impaired memory, and impaired concentration 5
• The 0.7 mg/kg three times daily dose causes significantly less sedation than higher doses (1.4 mg/kg three times daily) while maintaining equal efficacy 2

Seizure Risk

• In overdose situations, hydroxyzine can cause generalized seizures 6
• Use caution in patients with seizure disorders

Common Pitfalls to Avoid

• Do not use adult dosing (50-100 mg four times daily) in adolescents, as this exceeds the recommended pediatric maximum 1
• Do not abruptly escalate to maximum doses—gradual titration improves tolerability, particularly for sedation and dry mouth 4
• Do not combine with other CNS depressants without careful monitoring, as hydroxyzine is frequently found in combination with opioids and antidepressants in impairment cases 5
• Do not ignore cardiac symptoms—any palpitations or chest discomfort warrants immediate discontinuation and cardiac evaluation 3

Monitoring Recommendations

• Assess symptom control at 3-5 days and 2 weeks after initiation 2
• Monitor for excessive sedation, particularly during the first week of therapy 4, 2
• Evaluate for cardiac symptoms (palpitations, chest pain, tachycardia) at each follow-up 3
• Consider dose reduction if sedation persists beyond the first week 2