What is the recommended dosage and administration of Atarax (hydroxyzine) for sedation?

Hydroxyzine (Atarax) Dosage and Administration for Sedation

For sedation purposes, hydroxyzine (Atarax) is not recommended as a first-line agent due to safety concerns including QT prolongation risk and limited evidence supporting its efficacy compared to benzodiazepines.

Dosing Recommendations (When Used)

If hydroxyzine must be used for sedation:

Adult Dosing:

• Initial dose: 25-50 mg orally
• Timing: Administer 30-60 minutes before procedure
• Maximum daily dose: 100 mg divided into multiple doses
• Duration of effect: 4-6 hours

Pediatric Dosing:

• Oral dose: 0.5-1.0 mg/kg/dose
• Maximum: 50-100 mg per dose
• For moderate sedation: 3.7 mg/kg as a single oral dose 1

Safety Considerations

Contraindications:

• Patients with known QT prolongation
• Complete atrioventricular block
• Elderly patients with bradycardia
• Concurrent use of other QT-prolonging medications

Monitoring Requirements:

• Continuous pulse oximetry
• Blood pressure monitoring every 5-15 minutes
• Cardiac monitoring in high-risk patients
• Observation for paradoxical reactions

Preferred Alternatives for Sedation

Benzodiazepines:

• Midazolam:

  • Initial IV dose: 1-2 mg (0.03 mg/kg) over 1-2 minutes
  • Additional doses: 1 mg (0.2-0.3 mg) at 2-minute intervals until adequate sedation
  • Maximum total dose: Usually 6 mg 2
  • Continuous infusion: 0.5-1 mg/h, titrated to 1-20 mg/h as needed 2

• Lorazepam:

  • IV/IM: 0.05-0.15 mg/kg, may repeat hourly as needed
  • Maximum single dose: 5 mg 2

Procedural Considerations:

1. Establish IV access before sedation when possible
2. Administer sedatives in small, incremental doses
3. Allow sufficient time between doses to assess effect
4. Maintain IV access until patient is no longer at risk for cardiorespiratory depression 2

Important Cautions

• A case report documented torsade de pointes after administration of only 12.5 mg hydroxyzine in an elderly patient with complete atrioventricular block 3
• Hydroxyzine may cause QT prolongation and should be used with extreme caution in patients with cardiac disease
• When used for pediatric sedation, hydroxyzine showed no significant advantage when 20 mg was administered 24 hours before the procedure 1
• For critically ill ventilated patients requiring long-term sedation, enteral hydroxyzine (sometimes combined with lorazepam) may be considered as an alternative to continuous IV sedation after initial stabilization 4

Combination Therapy

When hydroxyzine is used in combination with other agents:

• Reduce doses of both medications to minimize adverse effects
• For pediatric dental procedures, midazolam alone (1.0 mg/kg) showed better overall sedation than midazolam (0.75 mg/kg) plus hydroxyzine (2.0 mg/kg) 5
• For EEG recordings in children, hydroxyzine (1.43±0.74 mg/kg) was equally effective as chloral hydrate for sleep induction 6

Remember that benzodiazepines, particularly midazolam, are generally preferred over hydroxyzine for procedural sedation due to their more predictable effects, established safety profile, and availability of reversal agents.