From the Guidelines
Yes, it is possible for an adult who has never had seizures to experience new-onset seizures while taking oxcarbazepine, although this is paradoxical since oxcarbazepine is an anticonvulsant medication typically used to treat seizures. This rare phenomenon can occur due to several mechanisms, including alterations in sodium channel activity or neurotransmitter levels that may trigger seizures in certain individuals 1. Key points to consider include:
- Drug interactions can also play a role if the person is taking other medications that lower the seizure threshold
- Rapid dose changes, especially sudden discontinuation, can precipitate seizures
- Underlying causes such as electrolyte disturbances, particularly hyponatremia, which is a known side effect of oxcarbazepine that can itself trigger seizures, should be investigated 1. If new-onset seizures occur while on oxcarbazepine, the patient should seek immediate medical attention, and the healthcare provider may need to adjust the medication, switch to a different anticonvulsant, or investigate other underlying causes. It's essential to weigh the benefits and risks of anticonvulsant medications, considering the potential side effects, such as cognitive impairment, neuropsychiatric disorders, fatigue, myelosuppression, liver dysfunction, dermatologic reactions, and interactions with systemic cancer treatment, as highlighted in the updated brain tumor seizure guidelines 1.
From the FDA Drug Label
- 11 Risk of Seizure Aggravation
Exacerbation of or new onset primary generalized seizures has been reported with oxcarbazepine. The risk of aggravation of primary generalized seizures is seen especially in children but may also occur in adults. In case of seizure aggravation, oxcarbazepine should be discontinued.
New onset seizures can occur in adults taking oxcarbazepine, as the drug label states that new onset primary generalized seizures have been reported with oxcarbazepine use, and this risk is not limited to children, but may also occur in adults 2.
From the Research
New Onset Seizures in Adults Taking Oxcarbazepine
- There is no direct evidence in the provided studies that suggests oxcarbazepine can cause new onset seizures in adults who have never had them before 3, 4, 5, 6, 7.
- The studies primarily focus on the efficacy and safety of oxcarbazepine in treating partial seizures and other types of epilepsy in adults and children, rather than its potential to induce new onset seizures in individuals without a history of epilepsy.
- Oxcarbazepine is generally considered to be a well-tolerated and effective antiepileptic drug, with common side effects including somnolence, dizziness, headache, nausea, and vomiting 3, 4, 5, 7.
- However, it is worth noting that oxcarbazepine can cause rare but serious side effects, such as hyponatremia and neurotoxicity, which may be related to its mechanism of action or individual patient factors 3, 5, 7.
Mechanism of Action and Pharmacokinetics
- Oxcarbazepine is a keto analog of carbamazepine, with a more favorable pharmacokinetic profile and minimal interaction with other antiepileptic drugs 4, 5, 7.
- It undergoes rapid and almost complete reductive metabolism to form its pharmacologically active 10-monohydroxy derivative, which is then glucuronidated and excreted in the urine 4, 5.
- The linear pharmacokinetics and lack of autoinduction of oxcarbazepine allow for standardized dose regimens and titration schedules in monotherapy and polytherapy 4, 7.
Clinical Use and Efficacy
- Oxcarbazepine is indicated for use as monotherapy or adjunctive therapy in the treatment of partial seizures with or without secondarily generalized seizures in adults and in children aged 6 and over 3, 5, 7.
- It has been shown to be effective in reducing seizure frequency and improving quality of life in patients with epilepsy, with a similar clinical antiepileptic efficacy to older antiepileptic drugs 3, 5, 7.