Trileptal (oxcarbazepine) is a highly effective antiepileptic medication. It is related to carbamazepine (Tegretol, Carbatrol), a widely used seizure medicine, and is used in similar situations. These include treating simple and complex partial seizures (with or without secondary generalization) and primary generalized tonic-clonic seizures. Comparisons of Trileptal and Tegretol have found them to be equally effective for these uses. Trileptal does not control absence seizures.

Many of the side effects commonly seen with Tegretol also are seen with Trileptal. In many people, Trileptal causes fewer and milder side effects than Tegretol or Carbatrol, however, so it may be substituted for those medications if side effects are a problem. Trileptal is much more expensive than Tegretol.

Some studies have compared Trileptal with other seizure medicines for treatment of newly diagnosed epilepsy. For instance, studies in both children and adults have compared Trileptal (used alone) with phenytoin (Dilantin, Phenytek) have found them to be about equally effective overall in controlling partial seizures and primary generalized tonic-clonic seizures. (About 60% of patients were seizure-free during the treatment period.) The patients who took Trileptal had fewer problems with side effects.

A similar study comparing Trileptal with Depakote (valproate) in adults found little difference between the two medications.

Trileptal also can be used as add-on therapy for patients whose seizures are not well controlled by one or two other medications. A summary of studies in which Trileptal was used in this way for partial seizures reported that 41% of adults who took Trileptal had their seizures reduced in frequency by at least half, compared to 13% of those who added a placebo to their previous medications.

A comparable study of add-on therapy for children also found that 41% of those who took Trileptal had at least a 50% decrease in seizure frequency. Of those who took a placebo, 22% had a similar reduction.

No single combination of medications is perfect for everyone. Sometimes, a series of combinations must be tried before finding what is best for the individual patient. If Trileptal is added to standard medications such as Tegretol or Depakote, usually no adjustment of the previous dosages of those medicines will be necessary. However, the dose of Dilantin (or Phenytek) may need to be decreased if Trileptal is added.