What is the recommended dosage and usage of hydroxyzine for treating anxiety and itching?

Hydroxyzine Dosing and Usage

For pruritus (itching), hydroxyzine 25 mg at bedtime is the recommended starting dose for adults, with the option to increase to 25 mg three to four times daily for daytime symptoms, while for anxiety, adults should receive 50-100 mg four times daily. 1

Pruritus Management

Dosing Strategy

• Adults: Start with 25 mg at bedtime for nighttime itching, which leverages hydroxyzine's sedative properties 2, 3
• For daytime symptoms: 25 mg three to four times daily 1
• Pediatric dosing:
  • Children under 6 years: 50 mg total daily dose divided throughout the day 1
  • Children over 6 years: 50-100 mg total daily dose in divided doses 1

Treatment Algorithm for Pruritus

• Mild/localized pruritus: Begin with topical treatments; add hydroxyzine 25 mg at bedtime if nighttime symptoms are problematic 3
• Moderate pruritus: Use non-sedating second-generation antihistamines during the day, reserve hydroxyzine for nighttime use 2, 3
• Severe/widespread pruritus: Consider combination therapy with H2 antihistamines and potentially GABA agonists (pregabalin, gabapentin 100-300 mg three times daily) 4, 3

Special Populations and Dose Adjustments

• Renal impairment: Reduce dose by 50% in moderate renal impairment 2, 3
• Severe liver disease: Avoid hydroxyzine due to inappropriate sedating effects 2, 3
• Elderly patients with cognitive impairment: Avoid due to anticholinergic effects 2
• Pregnancy: Contraindicated in early pregnancy 2, 3

Anxiety Management

Dosing for Anxiety

• Adults: 50-100 mg four times daily for symptomatic relief of anxiety and tension 1
• Pediatric dosing:
  • Children under 6 years: 50 mg total daily dose in divided doses 1
  • Children over 6 years: 50-100 mg total daily dose in divided doses 1

Efficacy Evidence

• Hydroxyzine demonstrates superiority over placebo for generalized anxiety disorder, with anxiolytic effects beginning within the first week of treatment 5
• The medication shows equivalent efficacy to benzodiazepines and buspirone for anxiety management 6
• Cognitive improvement may occur more rapidly with hydroxyzine compared to lorazepam 7

Common Adverse Effects and Management

Expected Side Effects

• Drowsiness/sleepiness: Most common side effect (28% vs 14% with placebo), typically transient and resolves during the first week of continued treatment 5
• Anticholinergic effects: Dry mouth (14% vs 5% with placebo), loss of concentration (9% vs 8%) 5
• Other effects: Weight gain (12% vs 10%), insomnia (9% vs 6%) 5

Key Clinical Advantages

• No organ toxicity or dependency potential with hydroxyzine 7
• No rebound anxiety or withdrawal symptoms after abrupt discontinuation 5
• Beneficial effects on sleep quality 7

Important Clinical Caveats

Avoid combining hydroxyzine with other sedating agents as this increases the risk of respiratory depression and apnea 4. When used in immune checkpoint inhibitor-related dermatologic toxicity, hydroxyzine can be safely combined with topical corticosteroids for enhanced symptom control 4.