What is the equivalent dose of Oxtellar XR (oxcarbazepine) when converting from Trileptal (oxcarbazepine)?

From the Guidelines

When converting from Trileptal to Oxtellar XR, the total daily dose remains the same, but Oxtellar XR is given once daily instead of twice daily, allowing for a direct 1:1 conversion. This is because both medications contain the same active ingredient, oxcarbazepine, but have different release mechanisms. For instance, if a patient is taking 600 mg of Trileptal twice daily (1200 mg total), they would take 1200 mg of Oxtellar XR once daily. The dosage of oxcarbazepine can be flexible, as the extent of satisfaction with the treatment is subjective and individualized, with some patients achieving complete remission with low-dose oxcarbazepine (75–300 mg/day) 1. Key considerations when making this conversion include:

• Monitoring patients for breakthrough seizures or side effects as the pharmacokinetic profile differs slightly between formulations
• Taking Oxtellar XR on an empty stomach, at least one hour before or two hours after meals
• The potential for improved tolerability and medication adherence due to the simplified once-daily dosing schedule of the extended-release formulation. Given the information provided, the study 1 does not directly address the conversion between Trileptal and Oxtellar XR, but it does discuss the use of oxcarbazepine in treating certain conditions, highlighting the importance of individualized treatment and flexible dosing.

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The concomitant AEDs should be completely withdrawn over 3 to 6 weeks, while the maximum dose of oxcarbazepine should be reached in about 2 to 4 weeks. Oxcarbazepine 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

The equivalent dose of Oxtellar XR (oxcarbazepine) when converting from Trileptal (oxcarbazepine) is the same dose, as both medications contain the same active ingredient, oxcarbazepine.

• The conversion can be done by maintaining the same daily dose,
• While simultaneously initiating the reduction of the dose of the concomitant antiepileptic drugs over 3 to 6 weeks. 2 2

From the Research

Conversion from Trileptal to Oxtellar XR

To convert from Trileptal (oxcarbazepine) to Oxtellar XR (oxcarbazepine), it is essential to understand the dosing and formulation of both medications.

• Oxtellar XR is an extended-release formulation of oxcarbazepine, whereas Trileptal is an immediate-release formulation.
• The recommended daily starting dose of oxcarbazepine for both mono- and adjunctive treatment is 8-10 mg/kg (600 mg/day for adults) in two doses and can be titrated according to clinical benefit up to 2400 mg/day 3.
• For adults, the clinically recommended titration scheme for all forms of therapy is to start with 150 mg/day at night and to increase by 150 mg/day every second day until a target dose of 900-1200 mg/day is reached 4.
• In children, treatment can be initiated with 8-10 mg/kg/day body weight in two to three divided doses, and dosage can be increased by 8-10 mg/kg/day in weekly increments if necessary for seizure control 4.
• The extended-release formulation of oxcarbazepine (Oxtellar XR) has been shown to have reduced peak-trough fluctuations compared to the immediate-release formulation (Trileptal) 5.
• When converting from Trileptal to Oxtellar XR, the dose may need to be adjusted to achieve the same therapeutic effect, as the extended-release formulation may have a different pharmacokinetic profile.

Dosing Considerations

• The dose of Oxtellar XR should be individualized based on the patient's response and tolerability.
• The recommended dose of Oxtellar XR is 150-600 mg/day, taken once daily 5.
• Patients who are already taking Trileptal may be converted to Oxtellar XR at the same total daily dose, but the dose may need to be adjusted based on the patient's response and tolerability.
• It is essential to monitor patients closely during the conversion process to ensure that the new dose is effective and well-tolerated.

Clinical Evidence

• Studies have shown that oxcarbazepine is effective and well-tolerated in the treatment of partial seizures, both as monotherapy and adjunctive therapy 3, 4, 6, 7.
• The extended-release formulation of oxcarbazepine (Oxtellar XR) has been shown to be effective and well-tolerated in clinical trials, with reduced peak-trough fluctuations compared to the immediate-release formulation (Trileptal) 5.