What is the difference between Atarax (hydroxyzine) and Vistaril (hydroxyzine) for treating anxiety and itching?

Atarax vs. Vistaril: Understanding the Difference

Atarax and Vistaril are the same medication (hydroxyzine) with different brand names, both effective for treating anxiety and pruritus (itching), with the primary difference being marketing and historical usage patterns rather than clinical efficacy.

What is Hydroxyzine?

Hydroxyzine is a first-generation H1 antihistamine that works by blocking histamine receptors. It has multiple therapeutic uses:

• For pruritus (itching): Effective for various allergic conditions including chronic urticaria and dermatoses 1
• For anxiety: Provides symptomatic relief of anxiety and tension associated with psychoneurosis 1
• As a sedative: Used as premedication before procedures 1

Key Properties of Hydroxyzine

• Sedation: Hydroxyzine causes significant sedation compared to second-generation antihistamines 2
• Anticholinergic effects: Can cause dry mouth, dry eyes, and constipation 2
• Duration of action: 4-6 hours for most effects
• Dosing: Typically 25-50 mg daily for adults, often divided throughout the day 2

Efficacy for Treating Pruritus

Hydroxyzine is recommended in clinical guidelines for:

• Mild to moderate pruritus: Particularly effective for nighttime itching due to its sedative properties 2
• Timing of use: First-generation antihistamines like hydroxyzine (25-50 mg daily) are recommended for nighttime use due to their sedative properties 2
• Treatment algorithm:
  1. For mild/localized pruritus: Start with topical treatments
  2. For moderate pruritus: Add oral antihistamines (hydroxyzine is specifically mentioned)
  3. For severe pruritus: Consider systemic treatments including antihistamines 2

Efficacy for Anxiety

Hydroxyzine has demonstrated effectiveness for anxiety disorders:

• Studies show it's more effective than placebo for generalized anxiety disorder (GAD) 3, 4
• In a 3-month double-blind study, hydroxyzine showed comparable efficacy to bromazepam (a benzodiazepine) for GAD 4
• Can be used as a substitute when withdrawing patients from benzodiazepines 5

Side Effects

Common side effects include:

• Drowsiness/sleepiness: Reported in up to 36% of patients 6
• Weakness: Reported in approximately 18% of patients 6
• Dry mouth: Less common but still reported 6
• Cognitive impairment: Can affect performance and driving ability 2

Special Considerations

• Pregnancy: Best avoided, especially in first trimester 2
• Liver disease: Use with caution in severe liver disease 2
• Renal impairment: Dose should be halved in moderate renal impairment 2
• Elderly patients: Increased sensitivity to anticholinergic effects 2

Common Pitfalls to Avoid

• Daytime sedation: Avoid using hydroxyzine during the day when alertness is required; consider second-generation antihistamines like loratadine for daytime use 2
• Prolonged use without reassessment: The effectiveness of hydroxyzine for anxiety beyond 4 months has not been systematically studied 1
• Combining with other CNS depressants: May enhance sedative effects when combined with alcohol or other sedatives 2
• Driving impairment: Patients should be warned about potential impairment of driving ability 2

Atarax vs. Vistaril: The Bottom Line

The only meaningful difference between Atarax and Vistaril is the brand name. Both contain the same active ingredient (hydroxyzine) and have identical clinical effects, side effect profiles, and dosing recommendations. The choice between them should be based on availability and cost rather than any clinical difference.