What is the best approach to transition a patient from Abilify (Aripiprazole) 5mg to Seroquel (Quetiapine)?

Transitioning from Abilify 5mg to Seroquel

The optimal approach for transitioning from Abilify (aripiprazole) 5mg to Seroquel (quetiapine) is a cross-titration method over 2 weeks, starting with 25mg of quetiapine while maintaining aripiprazole, then gradually increasing quetiapine while tapering aripiprazole.

Cross-Titration Protocol

Week 1:

• Days 1-3: Continue Abilify 5mg + Start Quetiapine 25mg at bedtime
• Days 4-7: Continue Abilify 5mg + Increase Quetiapine to 50mg at bedtime

Week 2:

• Days 8-10: Reduce Abilify to 2.5mg + Increase Quetiapine to 100mg at bedtime
• Days 11-14: Discontinue Abilify + Continue Quetiapine 100mg at bedtime

Week 3 and beyond:

• Titrate Quetiapine to target dose based on clinical indication and response
• For most conditions, target doses range from 150-400mg/day, given in divided doses or as a single bedtime dose

Dosing Considerations

• Initial Quetiapine Dose: Start with 25mg at bedtime to minimize side effects 1, 2
• Elderly Patients: Start with lower doses (25mg) and titrate more slowly in 25mg increments 2
• Hepatic Impairment: Start with 25mg and increase in smaller increments (25mg/day) 2
• Dosing Schedule: Quetiapine can be given twice daily or once daily (preferably at bedtime due to sedation) 3

Monitoring During Transition

Key Parameters to Monitor:

• Efficacy: Assess for symptom control during transition
• Sedation: Quetiapine is more sedating than aripiprazole; monitor for excessive daytime sleepiness
• Orthostatic Hypotension: Check blood pressure in sitting and standing positions
• Metabolic Parameters: Baseline and follow-up monitoring of weight, glucose, and lipids
• QTc Interval: Consider ECG monitoring in patients with cardiovascular risk factors

Potential Side Effects to Watch For:

• Sedation: More common with quetiapine than aripiprazole 1
• Orthostatic Hypotension: Particularly during initial titration of quetiapine 1
• Metabolic Effects: Quetiapine has higher risk of weight gain and metabolic changes compared to aripiprazole

Special Considerations

• Timing: Administer quetiapine at bedtime to capitalize on its sedative properties and improve sleep
• Breakthrough Symptoms: If psychotic or mood symptoms worsen during transition, consider temporarily slowing the taper of aripiprazole
• Drug Interactions: Assess for CYP3A4 inhibitors or inducers that may affect quetiapine metabolism 2
• Adherence Support: Educate patient about the importance of following the transition schedule and reporting side effects

Common Pitfalls to Avoid

1. Abrupt Discontinuation: Never stop aripiprazole abruptly as this may lead to withdrawal symptoms or rebound psychosis
2. Too Rapid Titration: Increasing quetiapine too quickly can lead to excessive sedation and orthostatic hypotension
3. Inadequate Monitoring: Failure to monitor for side effects during the transition period
4. Overlooking Drug Interactions: CYP3A4 inhibitors may increase quetiapine levels, requiring dose adjustment 2

This cross-titration approach balances the need to maintain symptom control while minimizing side effects during the transition between these two antipsychotics with different pharmacological profiles.