Epilepsy - Medications

Most side effects are mild to moderate and can be reduced or even prevented by beginning at low doses and increasing dosage gradually. Serious side effects may include glaucoma, decreased sweating, increased body temperature, kidney stones, sleepiness, dizziness, confusion, and trouble concentrating. Patients should immediately tell their doctor if they have blurred vision or eye pain.

text continues below

Oxcarbazepine. Oxcarbazepine (Trileptal) is similar to phenytoin and carbamazepine but generally has fewer side effects. It is approved as single therapy or add-on therapy for partial seizures in adults and for children aged 4 to 16 years. Serious side effects, while rare, include Stevens-Johnson syndrome and toxic epidermal necrolysis. These skin reactions cause a severe rash that can be life-threatening. Rash and fever may also be a sign of multi-organ hypersensitivity, another serious side effect associated with this drug. Oxcarbazepine can also reduce sodium levels (hyponatremia). Your doctor may want to monitor the sodium level in your blood. This drug can also reduce the effectiveness of birth control pills. Women who take oxcarbazepine may need to use a different type of contraceptive.

Zonisamide. Zonisamide (Zonegran) is a unique drug that blocks sodium and calcium channels and may have nerve-protecting properties. It is approved as add-on therapy for adults with partial seizures and studies indicate it is often effective against infantile spasms (West's syndrome) and myoclonic seizures. Zonisamide increases the risk for kidney stones, which can be reduced with increased fluid intake and citrate. It has also been associated with reduced sweating and a sudden rise in body temperature, especially in hot weather. Children are especially at risk for this side effect, which can be serious. (The drug has not been approved for children.) Other side effects tend to decrease over time and include dizziness, forgetfulness, headache, weight loss, and nausea.

Levetiracetam. Levetiracetam (Keppra) is known as a nootropic drug and has been approved for partial onset seizures in adults and children aged 4 years and older. Some experts believe that levetiracetam represents a significant advance and will prove to be an important first-line drug. Some evidence suggests that it improves mental function and quality of life. Levitracetam has fewer drug interactions than other anti-epileptic agents and may be particularly useful for older patients.

Side effects occur mostly in the first month. They include: sleepiness and fatigue, muscle weakness and coordination difficulties, headache, flu symptoms, dizziness, behavioral abnormalities, and possible risk of a reduced white blood cell count and a higher rate of infections. Caution is advised for patients with kidney dysfunction. There have been some reports of adverse effects on mood (irritability, depression, anxiety) but recent studies have found fewer such effects than with other AEDs. Epilepsy, rather than the drug, is likely to be the cause of these mood changes. About 1% of patients report considerable weight loss.