Hydroxyzine Dosage for Anxiety, Irritability with Anger, and Sleep
For anxiety and irritability with anger, start with hydroxyzine 50-100 mg divided into 4 doses daily (12.5-25 mg four times daily), and for sleep disturbances, administer 50-100 mg at bedtime. 1
Standard Dosing Regimen
For symptomatic relief of anxiety and tension:
- Adults: 50-100 mg four times daily (total daily dose 200-400 mg) 1
- The FDA-approved dosing specifically addresses psychoneurosis and organic disease states where anxiety manifests 1
- Clinical trials have demonstrated efficacy at a fixed dose of 50 mg with superiority over placebo on all anxiety measures from the first week of treatment 2
For elderly or sedative-sensitive patients:
- Start with 25 mg doses to minimize anticholinergic effects and excessive sedation 3, 4
- Elderly patients are more susceptible to anticholinergic side effects including confusion, urinary retention, and falls 4
Dosing Strategy for Combined Symptoms
When addressing anxiety, irritability, and sleep simultaneously:
- Administer 50-100 mg at bedtime to provide dual benefits for both anxiety control and sleep induction 3, 4
- This bedtime dosing capitalizes on hydroxyzine's sedative properties, with onset of action occurring within 15-30 minutes and effects lasting 4-6 hours 3, 4
- For daytime anxiety and irritability, add divided doses of 25-50 mg two to three times daily as needed 1
Mechanism and Clinical Advantages
Hydroxyzine works through H1-receptor antagonism and provides anxiolytic effects distinct from benzodiazepines 3. The anticholinergic effects may provide superior control of somatic anxiety symptoms such as trembling compared to second-generation antihistamines 3, 4. Research demonstrates that hydroxyzine produces greater and more rapid cognitive improvement compared to lorazepam 2.
Onset and Duration
- Onset: 15-30 minutes after oral administration 3, 4
- Duration: 4-6 hours 3, 4
- Clinical improvement in anxiety symptoms typically appears within the first week, with maintained efficacy throughout 4 weeks of treatment 2
Critical Precautions and Contraindications
Absolute contraindications:
- Closed-angle glaucoma 3, 4
- Prostatic hypertrophy 3, 4
- Early pregnancy (per UK manufacturer guidelines) 4
Use with extreme caution in:
- Elderly patients (increased anticholinergic sensitivity) 3, 4
- Cognitive impairment 3
- Severe hepatic or renal disease 4
Dose Adjustment and Titration
Adjust dosing based on clinical response rather than using fixed protocols 1. If initiating treatment for benzodiazepine withdrawal, hydroxyzine 50 mg daily significantly improves anxiety and reduces withdrawal symptomatology, while 25 mg daily is adequate for markedly anxious patients without prominent withdrawal symptoms 5.
Common Pitfalls to Avoid
- Do not underdose: The FDA-approved range of 50-100 mg four times daily for anxiety is substantially higher than many clinicians prescribe 1
- Avoid combining with other CNS depressants without dose adjustment, as additive sedation can occur 1
- Monitor for paradoxical agitation, particularly in younger patients, though this is rare 6
- Do not use as monotherapy for major depression—hydroxyzine does not constitute adequate treatment for comorbid major depressive disorder 6