Quetiapine (Seroquel) Dosing for Delirium
For delirium management, quetiapine should be initiated at 25 mg orally once daily and titrated up to 25-100 mg/day as needed, with most patients responding to doses between 25-50 mg/day. 1, 2
Initial Dosing
- Start with quetiapine 25 mg orally once daily, preferably at night due to sedating properties 1, 2
- For elderly patients or those with hepatic/renal impairment, consider starting at the lower end of the dosing range (25 mg) 1
- Immediate-release formulation is preferred for delirium management 1
Titration and Maintenance
- Dose can be increased gradually based on response and tolerability 2
- Effective dose range is typically 25-100 mg/day, with most patients responding to 45-50 mg/day 2, 3
- Divided dosing may be beneficial (e.g., twice daily) if agitation occurs throughout the day 4
- Duration of treatment is typically short-term until delirium resolves, with most patients responding within 4-5 days 3
Special Populations
- For elderly patients: Start at 25 mg daily with more cautious titration 1
- For critically ill patients: Low-dose prophylactic quetiapine (12.5-25 mg) has shown benefit in reducing delirium duration and improving outcomes 5, 6
- For patients unable to swallow: Consider alternative antipsychotics that can be administered parenterally, such as haloperidol or levomepromazine 7
Monitoring and Adverse Effects
- Monitor for common side effects including drowsiness, orthostatic hypotension, and somnolence 1, 4
- Quetiapine has advantages over typical antipsychotics including lower risk of extrapyramidal side effects 1, 3
- Transient hypotension may occur, particularly with rapid dose escalation 4
Alternative Options When Quetiapine Is Not Suitable
- Haloperidol 0.5-1 mg orally at night and every 2 hours as needed for patients who can swallow 7
- Levomepromazine 12.5-25 mg subcutaneously for patients unable to swallow 7
- Benzodiazepines alone are not recommended as first-line treatment for delirium but may be added for severe agitation refractory to antipsychotics 7, 1
Clinical Pearls
- Always address reversible causes of delirium first (e.g., hypoxia, urinary retention, constipation) 7
- Ensure effective communication, adequate lighting, and orientation to reduce delirium severity 7
- Antipsychotics themselves can potentially worsen delirium, so careful monitoring is essential 1
- Quetiapine has been shown to improve delirious conditions within 24 hours of treatment in many cases 2