Clinical Overview
Hydroxyzine is a first-generation antihistamine with anxiolytic properties indicated for the symptomatic relief of anxiety and tension associated with psychoneurosis and as an adjunct in organic disease states where anxiety is manifested. It is also used for allergic conditions, preoperative sedation, and antiemetic effects.
Primary Clinical Applications
Hydroxyzine is indicated for anxiety and tension, allergic conditions (urticaria, atopic dermatitis), preoperative and postoperative sedation, and nausea/vomiting. It is particularly valuable for short-term anxiety management and in patients where benzodiazepines are contraindicated or undesirable.
Mechanism and Clinical Benefits
Hydroxyzine blocks histamine H1 receptors and has anticholinergic and sedative properties. Its anxiolytic effects are thought to result from CNS depression rather than specific anxiolytic mechanisms. It provides anxiety relief without the dependence potential of benzodiazepines.
Safety Profile
Hydroxyzine has a favorable safety profile with low abuse potential and no risk of physical dependence. However, it can cause significant sedation and anticholinergic effects, particularly in elderly patients. Recent concerns about QT prolongation have led to dosing restrictions and monitoring recommendations.
Prescribing Information
Dosing & Administration
Anxiety and Tension:
- Adults: 50-100 mg 4 times daily
- Children ≥6 years: 50-100 mg daily in divided doses
- Children <6 years: 50 mg daily in divided doses
Pruritus (Itching):
- Adults: 25 mg 3-4 times daily
- Children ≥6 years: 50-100 mg daily in divided doses
- Children <6 years: 50 mg daily in divided doses
Preoperative Sedation:
- Adults: 50-100 mg
- Children: 0.6 mg/kg
Maximum Daily Dose:
- Adults: Use the lowest effective dose; consider a conservative maximum (e.g., ≤100 mg/day) in patients with QT risk factors or in older adults
- Elderly: Consider lower doses
Indications
- Symptomatic relief of anxiety and tension
- Allergic conditions (urticaria, atopic dermatitis)
- Preoperative and postoperative sedation
- Antiemetic
Contraindications
- Known hypersensitivity to hydroxyzine or cetirizine
- Early pregnancy
- QT prolongation or risk factors for QT prolongation
- Concurrent use of QT-prolonging medications
Warnings & Precautions
- QT prolongation/TdP risk: Avoid in patients with known QT prolongation, congenital long QT syndrome, significant bradycardia, recent MI, uncompensated heart failure, electrolyte abnormalities, or when used with other QT-prolonging drugs; use the lowest effective dose
- CNS depression: Avoid alcohol and other CNS depressants
- Anticholinergic effects: Use caution in elderly, glaucoma, BPH
- Seizure threshold: May lower in predisposed patients
- Acute angle-closure glaucoma: Risk in susceptible patients
Drug Interactions
- CNS depressants: Enhanced sedation
- QT-prolonging drugs: Increased arrhythmia risk
- Anticholinergic drugs: Additive anticholinergic effects
- MAOIs: Prolonged anticholinergic effects
Adverse Reactions
Common:
- Drowsiness, dry mouth, dizziness, blurred vision
Less Common:
- Confusion, headache, fatigue, nervousness
Serious:
- QT prolongation, torsades de pointes, seizures
Special Populations
- Pregnancy: Category C – avoid in early pregnancy
- Elderly: Increased sensitivity to anticholinergic effects
- Hepatic impairment: Reduce dose by 33%
- Cardiac disease: Monitor for QT prolongation
Medical Disclaimer: This information is for educational purposes only and is not intended as medical advice. Always consult with qualified healthcare professionals before making any treatment decisions. Individual patient circumstances may vary significantly.
