What is the recommended dose of hydroxyzine (hydroxyzine) for agitation?

Hydroxyzine Dosing for Agitation

For acute agitation in adults, hydroxyzine can be administered at an initial dose of 25-50 mg orally or intramuscularly, which may be repeated every 4-6 hours as needed, with a maximum daily dose of 400 mg.

Adult Dosing Guidelines

Initial Dosing

• Oral administration: 25-50 mg per dose
• Intramuscular (IM) administration: 25-50 mg per dose
• May repeat every 4-6 hours as needed

Maximum Dosing

• Maximum daily dose: 400 mg
• Consider lower doses in elderly patients (starting with 10-25 mg)

Special Populations

Elderly Patients

• Start with lower doses (10-25 mg)
• Increased risk of anticholinergic effects and sedation
• Monitor for confusion and falls

Hepatic Impairment

• Reduce dose by 25-50% due to decreased metabolism
• Monitor closely for excessive sedation

Clinical Considerations

Advantages of Hydroxyzine for Agitation

• Relatively safe with few serious side effects compared to antipsychotics 1
• No risk of extrapyramidal symptoms unlike typical antipsychotics
• Low addiction potential compared to benzodiazepines 2
• May be effective for agitation associated with anxiety

Limitations

• Onset of action is slower than benzodiazepines (20-30 minutes for oral, 15-30 minutes for IM) 2
• May cause significant sedation/drowsiness
• Has anticholinergic properties that may worsen delirium in some patients 2

Monitoring

• Assess level of sedation after administration
• Monitor vital signs, particularly in elderly patients
• Watch for paradoxical excitation (rare but possible)
• Observe for anticholinergic side effects (dry mouth, blurred vision, urinary retention)

Alternative Medications for Comparison

Benzodiazepines

• Lorazepam: 2 mg IM/IV/PO for adults, may repeat every 30-60 minutes 2
• Faster onset than hydroxyzine but higher risk of respiratory depression and paradoxical agitation

Antipsychotics

• Haloperidol: 5-10 mg IM for adults with severe agitation 2
• More effective for psychotic agitation but higher risk of extrapyramidal symptoms

Combination Therapy

• For severe agitation not responding to hydroxyzine alone, consider combination therapy
• The American College of Emergency Physicians notes that combination therapy with a benzodiazepine and antipsychotic may be more effective than monotherapy for severe agitation 3

Common Pitfalls and Caveats

• Hydroxyzine may worsen conditions with anticholinergic features (e.g., delirium)
• Avoid in patients with known QT prolongation
• Use cautiously in patients with respiratory conditions as it may cause mild respiratory depression
• May have additive effects when combined with other CNS depressants
• Rare cases of catatonia have been reported with hydroxyzine overdose 4

While hydroxyzine is generally well-tolerated, it may not be sufficient for severe agitation, particularly in psychotic patients or those with severe manic episodes, where antipsychotics or benzodiazepines may be more appropriate first-line agents.