Maximum Daily Dose of Seroquel (Quetiapine)
The maximum daily dose of Seroquel (quetiapine) for adults is 800 mg/day for schizophrenia and bipolar mania, and 300 mg/day for bipolar depression. 1
Indication-Specific Maximum Doses
The FDA-approved maximum doses vary by indication:
Schizophrenia
- Adults: Maximum dose is 750 mg/day 1
- Adolescents (13-17 years): Maximum dose is 800 mg/day 1
- Typical dosing range is 150-750 mg/day, with most patients responding to 300-400 mg/day by Day 4 of titration 1
Bipolar Mania
- Adults (monotherapy or adjunct to lithium/divalproex): Maximum dose is 800 mg/day 1
- Children and Adolescents (10-17 years): Maximum dose is 600 mg/day 1
- Effective dose range is typically 400-800 mg/day for adults 1
Bipolar Depression
- Adults: Maximum dose is 300 mg/day, administered once daily at bedtime 1
- This is notably lower than for other indications 1
Maintenance Therapy
- Bipolar I Disorder: 400-800 mg/day (maximum 800 mg/day) as adjunct to lithium or divalproex 1
- Schizophrenia: 400-800 mg/day (maximum 800 mg/day) 1
Special Population Considerations
Elderly Patients
- Start at 50 mg/day with increments of 50 mg/day 1
- The American Academy of Family Physicians recommends a maximum of 200 mg twice daily (400 mg/day total) for elderly patients 2
- Slower titration is essential due to increased risk of orthostatic hypotension and sedation 2
Hepatic Impairment
- Start at 25 mg/day with daily increments of 25-50 mg/day to effective dose 1
- Maximum dose should be lower than standard adult dosing, though specific ceiling not defined in labeling 1
Drug Interactions with CYP3A4 Inhibitors
- When co-administered with potent CYP3A4 inhibitors (ketoconazole, itraconazole, ritonavir), reduce dose to one-sixth of original dose 1
- For example, if on 600 mg/day, reduce to 100 mg/day 1
Clinical Context from Research
Research supports these maximum doses, with studies demonstrating:
- Doses up to 750 mg/day are effective and well-tolerated in schizophrenia 3, 4
- The 150-750 mg/day range provides optimal efficacy with placebo-level extrapyramidal symptoms across the entire dose range 3
- Higher doses (≥400 mg/day) should be used in patients who do not fully respond to lower doses 5
Critical Safety Points
Do not exceed 800 mg/day even in treatment-resistant cases, as this exceeds FDA-approved maximum dosing and increases risk without established additional benefit 1. The exception is bipolar depression, where 300 mg/day is the absolute ceiling 1.