Key takeaways
Trileptal (oxcarbazepine) and zonisamide (Zonegran) are both antiepileptic medications used to treat partial-onset seizures, but they have some key differences. Trileptal is available in both immediate-release and extended-release (Oxtellar XR) forms, and it can be used alone or with other seizure medications. The immediate-release form is suitable for children as young as 2 years old. On the other hand, zonisamide is typically used as an add-on treatment and is only approved for people aged 16 and older. Trileptal can cause dizziness, nausea, and headaches, while zonisamide may lead to sleepiness, dizziness, and loss of appetite. Additionally, zonisamide carries a risk of serious allergic reactions in people with sulfa allergies (eg, Bactrim). Both medications can cause serious skin reactions and increase the risk of suicidal thoughts, but zonisamide also has specific warnings about heat stroke and kidney problems. Both medications are available as lower-cost generics, with the exception of the brand-name oral suspension of zonisamide (Zonisade).
