How to cross-taper from Gio Dan 80 mg BID to Seroquel (quetiapine) XR?

Cross-Tapering from Geodon 80 mg BID to Seroquel XR

When cross-tapering from Geodon (ziprasidone) 80 mg BID to Seroquel XR (quetiapine extended-release), gradually decrease Geodon while simultaneously increasing Seroquel XR over a 2-4 week period to minimize withdrawal symptoms and maintain symptom control.

Cross-Tapering Protocol

Week 1:

• Decrease Geodon to 60 mg BID
• Start Seroquel XR 50 mg at bedtime

Week 2:

• Decrease Geodon to 40 mg BID
• Increase Seroquel XR to 100 mg at bedtime

Week 3:

• Decrease Geodon to 20 mg BID
• Increase Seroquel XR to 200 mg at bedtime

Week 4:

• Discontinue Geodon
• Increase Seroquel XR to 300-400 mg at bedtime (target therapeutic dose)

Rationale and Considerations

1. Initial Dosing: Start with a low dose of Seroquel XR (50 mg) to minimize side effects while maintaining partial Geodon coverage 1. The FDA drug label recommends starting with lower doses and gradually titrating up.

2. Gradual Titration: Quetiapine requires careful titration to minimize side effects such as sedation, dizziness, and orthostatic hypotension 2, 1. The American Family Physician guidelines recommend starting with lower doses in elderly or debilitated patients.

3. Monitoring Parameters:

   • Sedation and orthostatic hypotension (particularly during the first few days)
   • Extrapyramidal symptoms (EPS)
   • Metabolic parameters (blood glucose, lipids)
   • QTc interval (both medications can affect cardiac conduction)

4. Special Considerations:

   • If the patient experiences significant sedation, consider administering more of the Seroquel XR dose at bedtime
   • If orthostatic hypotension occurs, slow the titration schedule
   • Monitor for withdrawal symptoms from Geodon (insomnia, anxiety, irritability)

Common Pitfalls to Avoid

1. Too rapid discontinuation of Geodon can lead to withdrawal symptoms or rebound psychosis. The cross-taper should be gradual.

2. Starting with too high a dose of Seroquel XR can cause excessive sedation, orthostatic hypotension, and poor tolerability 2.

3. Failure to monitor for drug interactions. If the patient is on CYP3A4 inhibitors or inducers, the Seroquel dose may need adjustment 1.

4. Inadequate patient education about expected side effects, particularly increased sedation when transitioning to Seroquel XR.

Final Dosing Considerations

The final target dose of Seroquel XR should be based on the indication and clinical response:

• For schizophrenia: 400-800 mg/day is typically effective 1
• For bipolar disorder: 300-600 mg/day is often sufficient 2
• For adjunctive use in other conditions: 150-300 mg/day may be adequate

Quetiapine has a favorable side effect profile regarding extrapyramidal symptoms compared to typical antipsychotics, with placebo-level incidence of EPS across its entire dose range 3, making it potentially advantageous for patients who experienced EPS on other antipsychotics.