National Stroke Foundation

Trileptal (oxcarbazepine) Tablets

The following drug information is obtained from various newswires, published medical journal articles, and medical conference presentations.


Approval Status:

Approved January 2000

Specific Treatments:

Adjunctive & monotherapy in adults; adjunctive therapy for children ages 4-16 with partial epileptic seizures

General Information

Trileptal, an anticonvulsant or antiepileptic drug (AED), was approved for use as an adjunctive and monotherapy for the treatment of partial seizures in adults with epilepsy and for the adjunctive treatment of partial seizures in children, ages 4-16, with epilepsy. It is the first AED to be approved as a monotherapy in several years.

2.3 million Americans have been diagnosed with epilepsy. This year, 181,000 more Americans (children and adults) will develop epilepsy and seizures.

Clinical Results

Recent trials include 6 multi-center randomized double blind controlled trials that were conducted to determine the effectiveness of the drug. 4 of the studies investigated the drug as a monotherapy. Participants in these trials ranged from 8 to 66 years old. Two of the studies tested the drug as an adjunctive therapy.

In studies in which the drug was compared to a placebo, patients given the drug lasted significantly longer without having certain seizures than did those patients not taking the drug.

Furthermore, a higher dosage of the drug yielded a significantly longer period before the patient demonstrated specific seizure symptoms.

In addition, two trials, one in which patients were ages 15-66 and the other in which patients were ages 3-17, examined Trileptal as an adjunctive therapy. Every patient in these trials was on 1-3 concomitant Anti-Epileptic Drugs. In both studies, dosage was increased over a period of two weeks until the patient reached the assigned dose or experienced an intolerance to the dosage.

Results of the pediatric trial indicated that compared to a placebo, patients taking the study medication experienced over 25% greater reduction of frequency of partial seizures.

In the adult study, the reduction of frequency of partial seizures for those taking the study drug at the lowest dose was over 18% greater than those taking the placebo, while at the highest dose was over 42% greater than those taking the placebo.

Side Effects

The most common side effects include, but are not limited to:

  • Headache
  • Somnolence or fatigue
  • Dizziness
  • Viral Infection
  • Nausea

Some patients also exhibited hyponatremia (low serum sodium levels). Most patients who developed this side effect, were asymptomatic. In clinical trials, patients whose treatment was discontinued due to hyponatremia, generally experienced normalization of serum sodium within a few days without additional treatment.

Some additional side effects were associated with the central nervous system (CNS). These include:

  • Psychomotor slowing
  • Difficulty with concentration
  • Speech or language problems
  • Coordination abnormalities

In clinical trials, patients' discontinuation of therapy due to these CNS side effects was dose related when the drug was used as an adjunctive therapy; higher dosages increased the discontinuation rate. No discontinuation of treatment due to similar side effects was found when the drug was used as a monotherapy.

Trileptal should not be used in patients with a known hypersensitivity to oxcarbazepine or to any of its components.

Mechanism of Action

The pharmacological activity of Trileptal (oxcarbazepine) is primarily exerted through the 10-monohydroxy metabolite (MHD) of oxcarbazepine… The precise mechanism by which oxcarbazepine and MHD exert their antiseizure effect is unknown; however in vitro electrophysiological studies indicate that they produce blockade of voltage-sensitive sodium channels, resulting in the stabilization of hyperexcited neural membranes, inhibition of repetitive neuronal firing, and dimunition of propagation of synaptic impulses. These actions are thought to be important in the prevention of seizure spread in the intact brain. In addition, increased potassium conduction and modulation of high-voltage activated calcium channels may contribute to the anticonvulsive effects of the drug. No significant interactions of oxcarbazepine or MHD with brain neurotransmitter or modulator receptor sites have been demonstrated. (from FDA Label)

Literature References

For more information about epilepsy, visit the official web site of the Epilepsy Foundation, a non-profit volunteer agency devoted to research, education, advocacy, and services in the community for people with epilepsy and their families:

or visit, where you can find out about everything from dates of international conferences about epilepsy to a list of countries where Trileptal is available.

Additional Information

This is what the Epilepsy Foundation says to do and not to do if you encounter a person having an epileptic seizure:

What To Do:

  • Look for medical identification.
  • Protect from nearby hazards.
  • Loosen ties or shirt collars.
  • Protect head from injury.
  • Turn on side to keep airway clear unless injury exists.
  • Reassure as consciousness returns.
  • If a single seizure lasted less than 5 minutes, ask if hospital evaluation wanted.
  • If there are multiple seizures, or if one seizure lasts longer than 5 minutes, call an ambulance.
  • If person is pregnant, injured, or diabetic, call for aid at once.

What Not To Do:

  • Don't put any hard implement in the mouth.
  • Don't try to hold tongue. It can't be swallowed.
  • Don't try to give liquids during or just after seizure,
  • Don't use artificial respiration unless breathing is absent after muscle jerks subside, or unless water has been inhaled.
  • Don't restrain.