What is the recommended dosage of Hydroxyzine for itching and anxiety?

Hydroxyzine Dosing for Pruritus and Anxiety

For pruritus, use hydroxyzine 25 mg three to four times daily in adults; for anxiety, use 50-100 mg four times daily in adults. 1

Pruritus Management

Adult Dosing

• Standard dose: 25 mg three to four times daily (TID or QID) for management of pruritus due to allergic conditions including chronic urticaria, atopic dermatitis, and contact dermatoses 1
• Hydroxyzine is particularly effective as a nighttime agent due to its sedative properties, which help patients sleep despite itching 2
• Non-sedating second-generation antihistamines should be used for daytime pruritus control, with hydroxyzine reserved for nighttime use 2

Pediatric Dosing for Pruritus

• Children under 6 years: 50 mg daily in divided doses 1
• Children over 6 years: 50-100 mg daily in divided doses 1

Special Considerations for Pruritus

• Reduce dose by 50% in moderate renal impairment (eGFR considerations) 2
• The British Association of Dermatologists supports hydroxyzine for generalized pruritus, noting significant improvement in symptoms and quality of life when used as nighttime medication 2
• If inadequate response occurs, consider increasing dose, adding H2 antihistamines, or switching to alternative treatments 2

Anxiety Management

Adult Dosing

• Standard dose: 50-100 mg four times daily (QID) for symptomatic relief of anxiety and tension associated with psychoneurosis 1
• Clinical trials demonstrate efficacy at fixed dose of 50 mg daily in generalized anxiety disorder, with superiority over placebo evident from the first week of treatment 3, 4
• Anxiolytic effects commence during the first week and are maintained throughout 4-week treatment periods without rebound anxiety or withdrawal symptoms upon abrupt discontinuation 4

Pediatric Dosing for Anxiety

• Children under 6 years: 50 mg daily in divided doses 1
• Children over 6 years: 50-100 mg daily in divided doses 1

Dosing Strategy to Minimize Side Effects

Evening or bedtime dosing (50 mg at bedtime) significantly reduces daytime sedation and psychomotor impairment while maintaining therapeutic efficacy 5

• This strategy maintains H1-receptor antagonism the following morning 5
• Alleviates reaction time prolongation seen with divided daytime doses 5
• Transient drowsiness typically appears during the first week but progressively diminishes with continued treatment 4

Critical Contraindications and Precautions

Absolute Avoidance

• Avoid in severe liver disease due to inappropriate sedating effects 2
• Contraindicated in early pregnancy 2
• Avoid in elderly patients with cognitive impairment due to anticholinergic effects 2

Common Side Effects

• Drowsiness (28% vs 14% placebo), typically transient 4
• Dry mouth (14% vs 5% placebo) 4
• Weight gain (12% vs 10% placebo) 4
• Loss of concentration (9% vs 8% placebo) 4

Dose Adjustment Algorithm

Adjust dosage according to patient response to therapy, as with all potent medications 1

• Start with standard dosing based on indication (pruritus vs anxiety) 1
• For pruritus: Consider nighttime-only dosing initially to assess tolerance 2, 5
• For anxiety: May initiate at 50 mg daily and titrate to 50-100 mg QID based on response 1, 3
• Reduce dose by 50% in moderate renal impairment 2