What is the proper procedure for switching from Trileptal (oxcarbazepine) to Oxtellar (oxcarbazepine)?

From the Guidelines

The proper procedure for switching from Trileptal (immediate-release oxcarbazepine) to Oxtellar XR (extended-release oxcarbazepine) involves a direct conversion at the same total daily dose, but with Oxtellar XR given once daily instead of the twice-daily Trileptal regimen. For example, if you're currently taking 600 mg of Trileptal twice daily (1200 mg total), you would switch to 1200 mg of Oxtellar XR once daily. This transition should be done under medical supervision, and the switch is typically made overnight - take your last dose of Trileptal in the evening, then start Oxtellar XR the next morning. No tapering is generally required since both medications contain the same active ingredient (oxcarbazepine), just in different formulations. The extended-release formulation of Oxtellar provides more consistent blood levels throughout the day, which may improve seizure control and reduce side effects for some patients, as seen in the management of paroxysmal kinesigenic dyskinesia where oxcarbazepine treatment has reported a complete or partial relief of attacks 1. It's essential to monitor for any changes in seizure frequency or side effects during the transition period. If you experience any issues, contact your healthcare provider immediately, as dosage adjustments may be necessary. Some patients may benefit from a brief overlap period where both medications are taken for 1-2 days, but this should only be done if specifically directed by your doctor. Key considerations in this transition include:

• Direct conversion at the same total daily dose
• Medical supervision
• Overnight switch from Trileptal to Oxtellar XR
• Monitoring for changes in seizure frequency or side effects
• Potential for brief overlap period if directed by a healthcare provider
• Importance of individualized treatment and communication regarding prognosis, adverse effects, and expected outcomes, as emphasized in the management of epilepsy and associated intellectual disability 1.

From the FDA Drug Label

The concomitant AEDs should be completely withdrawn over 3 to 6 weeks, while the maximum dose of oxcarbazepine should be reached in about 2 to 4 weeks. To switch from Trileptal (oxcarbazepine) to Oxtellar (oxcarbazepine),

• Concomitant AEDs (in this case Trileptal) should be completely withdrawn over 3 to 6 weeks.
• The dose of Oxtellar may be increased as clinically indicated by a maximum increment of 600 mg/day at approximately weekly intervals to achieve the maximum recommended daily dose of 2,400 mg/day.
• Patients should be observed closely during this transition phase 2.

From the Research

Switching from Trileptal to Oxtellar

To switch from Trileptal (oxcarbazepine) to Oxtellar (oxcarbazepine), it is essential to understand that both medications are essentially the same active ingredient, oxcarbazepine, but may have different formulations or release mechanisms. The key considerations include:

• Dose Equivalence: Ensure that the dose of Oxtellar is equivalent to the dose of Trileptal being taken. The recommended daily dose for both medications can vary, but they are generally in the range of 600 mg/day to 2400 mg/day for adults, divided into two doses 3, 4.
• Titration: If switching from one formulation to another, it may be necessary to titrate the dose to achieve the optimal therapeutic effect while minimizing side effects. The titration scheme can start with 150 mg/day at night and increase by 150 mg/day every second day until a target dose is reached 4, 5.
• Monitoring: During the switch, monitor for any changes in seizure frequency or side effects. Hyponatremia (low sodium levels) is a potential side effect that may require monitoring, especially if the patient has renal disease or is taking other medications that can lower sodium levels 4, 6.
• Drug Interactions: Oxcarbazepine has a relatively low potential for drug interactions compared to older antiepileptic drugs, but it can interact with certain medications, such as phenytoin and oral contraceptives. Monitoring and potential dose adjustments of concomitant medications may be necessary 6, 7.

Key Considerations for Switching

• Pharmacokinetics: Oxcarbazepine is rapidly reduced to its active metabolite, MHD. The pharmacokinetics of oxcarbazepine and MHD are linear, with no autoinduction, which simplifies the switching process 7.
• Therapeutic Range: A mean therapeutic range of 15-35 mg/L for MHD is considered appropriate, but individual variations may occur. Therapeutic monitoring can help in managing the switch and adjusting doses as needed 7.

Practical Steps for Switching

• Consult with a healthcare provider before making any changes to medication.
• Ensure the equivalent dose of Oxtellar is prescribed based on the current Trileptal dose.
• Follow the recommended titration schedule if necessary.
• Monitor for side effects and changes in seizure control.
• Adjust concomitant medications as necessary based on potential interactions with oxcarbazepine.