Quetiapine (Seroquel) Dosing for Depression
For depression, the recommended dose of quetiapine is 300 mg/day, administered once daily at bedtime, with initial titration starting at 50 mg on day 1, increasing to 100 mg on day 2,200 mg on day 3, and reaching 300 mg on day 4. 1
Dosing Protocol for Depression
The FDA-approved dosing schedule for quetiapine in bipolar depression follows a specific titration pattern:
- Day 1: 50 mg once daily at bedtime 1
- Day 2: 100 mg once daily at bedtime 1
- Day 3: 200 mg once daily at bedtime 1
- Day 4: 300 mg once daily at bedtime 1
- Maintenance dose: 300 mg/day 1, 2
Evidence for Efficacy in Depression
- Quetiapine has demonstrated efficacy in treating depressive symptoms at doses of 300 mg/day for bipolar depression 2
- For unipolar depression, studies have found quetiapine to be effective at doses of approximately 150-300 mg per day 3
- The extended-release (XR) formulation has also shown efficacy at 300 mg/day for depression 4
Important Clinical Considerations
Titration and Administration
- Quetiapine can be taken with or without food 1
- Slower titration may be needed in elderly patients, starting at 50 mg/day with careful increases 1
- Hepatically impaired patients should start at 25 mg/day with careful titration 1
Augmentation Therapy
- When used as augmentation to antidepressants in treatment-resistant depression, doses between 50-300 mg/day have shown benefit 5
- One study using quetiapine augmentation (200-600 mg nocte) reported rapid improvement in depression ratings and high remission rates 6
Potential Side Effects
- Most common side effects include dry mouth, sedation, somnolence, dizziness, and constipation 2
- Metabolic effects: Even low doses may lead to increases in weight and triglycerides 3
- Due to sedative properties, quetiapine is typically administered at bedtime 1
Monitoring
- Regular monitoring of weight, blood glucose, and lipid parameters is recommended 2, 3
- Extrapyramidal symptoms are less common with quetiapine compared to typical antipsychotics 2
Special Populations
- Elderly patients: Start at 50 mg/day and increase cautiously in increments of 50 mg/day 1
- Hepatic impairment: Start at 25 mg/day and increase in increments of 25-50 mg/day 1
- With CYP3A4 inhibitors: Reduce dose to one-sixth of original dose 1
- With CYP3A4 inducers: May need to increase dose up to 5-fold 1
Remember that while quetiapine is FDA-approved for bipolar depression at 300 mg/day, its use in unipolar depression may be off-label in some jurisdictions, though clinical evidence supports its efficacy in this indication as well 3, 5, 4.