Hydroxyzine
General
- Type: Antihistamines / H1 blocker
- Dosage Forms: Oral, IM
- Common Trade Names: Atarax
Adult Dosing
- Anxiety
- PO: 50-100mg q6h PRN
- IM: 50-100mg q4-6h PRN
- Allergic reaction or Pruritus
- PO: 25mg q6-8h
- Insomnia
- PO: 50-100mg PO qhs
- IM: 50mg qhs
Pediatric Dosing
- Anxiety or Pruritus
- <6 yo
- PO: 50mg/day divided into q6-8h PRN
- 6-12 yo
- PO: 50-100mg/day divided into q6-8h PRN
- >12 yo
- See adult dosing
- <6 yo
Special Populations
- Pregnancy Rating: No human data available
- Renal Dosing: CrCl <50: decrease usual dose by 50%
- Hepatic Dosing: n/a
Contraindications
- Allergy to class/drug
- Elderly patients
- QT prolongation
Adverse Reactions
Serious
- Anticholinergic toxicity
- CNS depression
- Seizures
- Torsades de pointes
Common
- Sedation
- Dizziness
- Headache
Pharmacology
- Half-life: Children 7 hours, Adults 3-20 hours, Elderly >20 hours
- Metabolism: Hepatic, CYP450
- Excretion: Urine
- Mechanism of Action: Nonselective antagonism of central/peripheral H1 receptors