Quetiapine Dosing for Bipolar Disorder
For bipolar disorder, quetiapine should be initiated at 50mg on day 1, increased to 100mg on day 2, 200mg on day 3, and then titrated to a target dose of 300-600mg/day for bipolar depression or 400-800mg/day for mania, with most patients requiring the higher end of these ranges for optimal efficacy.
Dosing by Episode Type
Bipolar Depression
- Starting dose: 50mg once daily at bedtime
- Titration schedule:
- Day 1: 50mg at bedtime
- Day 2: 100mg at bedtime
- Day 3: 200mg at bedtime
- Day 4: 300mg at bedtime
- Target dose: 300mg once daily 1
- Maximum dose: 600mg daily (no additional benefit observed at higher doses) 1, 2
Bipolar Mania/Mixed Episodes
- Starting dose: 50mg once daily at bedtime
- Titration schedule:
- Day 1: 50mg at bedtime
- Day 2: 100mg at bedtime
- Day 3: 200mg at bedtime
- Day 4: 300mg at bedtime
- Day 5: 400mg at bedtime
- Further titration as needed
- Target dose: 400-800mg daily 3, 4
- Maximum dose: Most clinical trials used 800mg daily maximum, though higher doses (>800mg) have been used in clinical practice for mixed episodes 5
Extended-Release (XR) Formulation
- Bipolar depression: 300mg once daily in the evening
- Bipolar mania:
- Day 1: 300mg
- Day 2: 600mg
- Day 3 onward: 400-800mg once daily (flexible dosing) 3
Special Considerations
Efficacy Timing
- Antimanic effects may begin as early as day 4 of treatment 3
- Antidepressant effects typically require 1-2 weeks to become apparent 1
Dose-Response Relationship
- For bipolar depression: No significant difference in efficacy between 300mg and 600mg daily doses 1
- For bipolar mania: Most responders (84%) require doses between 400-800mg daily 4
Mixed Episodes
- Higher doses of quetiapine (>800mg daily) may be required for mixed episodes 5
- Mixed episodes are a significant predictor of requiring higher quetiapine dosages
Monitoring and Side Effects
Common Side Effects
- Sedation (dose-dependent)
- Dry mouth
- Somnolence
- Dizziness
- Constipation
- Increased appetite
Metabolic Monitoring
- Baseline and periodic monitoring of:
- Weight and BMI
- Blood pressure
- Fasting glucose
- Lipid panel
Extrapyramidal Symptoms
- Lower risk compared to typical antipsychotics like haloperidol 4
- Rates similar to placebo in clinical trials 1
Maintenance Treatment
- Continue same dose that was effective during acute treatment
- Maintenance treatment significantly reduces risk of recurrence of mood episodes, particularly depressive episodes 2
- Long-term treatment (26-52 weeks) shows continued efficacy with similar tolerability profile 2
Practical Tips
- Administer at bedtime to minimize daytime sedation
- More sedating than many other antipsychotics; can be beneficial for patients with insomnia
- Beware of transient orthostasis, particularly in elderly patients 6
- For elderly patients or those with hepatic impairment, use lower starting doses and titrate more slowly
Common Pitfalls to Avoid
- Underdosing: Many patients require the full 300mg for depression or 600mg for mania
- Too rapid titration: Follow recommended titration schedule to minimize side effects
- Inadequate duration of treatment: Continue effective dose for maintenance to prevent relapse
- Failure to monitor metabolic parameters: Regular monitoring is essential
Quetiapine is an effective monotherapy option for both the acute and maintenance treatment of bipolar disorder, with demonstrated efficacy in both manic and depressive episodes when dosed appropriately.