Hydroxyzine Hydrochloride
Generic Details
Generic Name
Hydroxyzine Hydrochloride
Other Names
- Atarax
- Vistaril
Drug Class
- Antihistamine
- Anxiolytic
Chemical Formula
C21H27ClN2O2
Molecular Weight
374.91 g/mol
Mechanism of Action
- Blocks histamine H1 receptors
- Acts as a serotonin receptor antagonist
Indications
- Anxiety disorders
- Allergic reactions
- Pruritus
- Nausea and vomiting
- Sedation
- Generalized anxiety disorder (off-label)
Common Dosage Forms
- Tablet
- Capsule
- Syrup
Typical Dosage
- 25-50 mg 3-4 times daily for anxiety
- 10-50 mg for pruritus and allergic reactions
Pediatric Dosage
- 0.5 mg per kg per day divided into 3-4 doses for children
Geriatric Dosage
- Lower doses may be required due to decreased drug clearance
Side Effects
- Drowsiness
- Dry mouth
- Blurred vision
- Constipation
- Urinary retention
- Headache
Contraindications
- Hypersensitivity to hydroxyzine
- Porphyria
- Severe liver disease
Pregnancy Category
- C - Risk cannot be ruled out
Lactation Safety
- May pass into breast milk, caution advised
Drug Interactions
- Sedatives
- Tricyclic antidepressants
- MAO inhibitors
- Alcohol
Overdose Symptoms
- Confusion
- Hallucinations
- Seizures
- Cardiac arrhythmias
Antidote for Overdose
- No specific antidote, symptomatic treatment
Storage Conditions
- Store at room temperature away from moisture and heat
Pharmacokinetics
- Absorption: Well absorbed from the gastrointestinal tract
- Distribution: Crosses the blood-brain barrier and placenta; found in breast milk
- Metabolism: Metabolized in the liver to its active metabolite cetirizine
- Excretion: Excreted primarily in the urine
Precautions
- Caution in patients with narrow-angle glaucoma
- Use with caution in the elderly due to increased risk of sedation and hypotension
Warnings
- May impair activities requiring mental alertness
- Avoid alcohol consumption while taking hydroxyzine
Others
- Hydroxyzine is also used in the management of opioid and alcohol withdrawal symptoms