From the Guidelines
Oxcarbazepine is an anticonvulsant medication primarily used to treat seizures in epilepsy, particularly partial seizures, and is often preferred for patients with PRRT2 mutations, such as those with paroxysmal kinesigenic dyskinesia (PKD) or benign familial infantile epilepsy (BFIE) 1.
Key Points About Oxcarbazepine
- Oxcarbazepine works by decreasing abnormal electrical activity in the brain by blocking sodium channels, which helps prevent the spread of seizure activity.
- The medication can be used alone or in combination with other seizure medications, and its use is supported by recent expert consensus 1.
- Common side effects include dizziness, drowsiness, nausea, vomiting, headache, double vision, and problems with coordination.
Important Considerations
- Patients should be aware that oxcarbazepine can reduce the effectiveness of hormonal contraceptives, so alternative birth control methods may be necessary.
- It may also cause hyponatremia (low sodium levels), so monitoring sodium levels is important, especially when starting treatment 1.
- Patients should take this medication regularly as prescribed and not stop suddenly without medical supervision, as this could trigger seizures.
Dosage and Administration
- The typical starting dose for adults is 300 mg twice daily, gradually increasing to an effective dose, usually between 1200-2400 mg per day divided into two doses.
- For children, dosing is based on weight, and should be determined by a healthcare professional.
Clinical Context
- In the context of BFIE or PKD, carbamazepine or oxcarbazepine tends to be the preferred anti-epileptic drug (AED) due to the known favorable response in patients with PKD 1.
From the FDA Drug Label
Oxcarbazepine, USP is an antiepileptic drug available as 150 mg, 300 mg, and 600 mg film-coated tablets for oral administration. Oxcarbazepine is 10,11-Dihydro-10-oxo-5H-dibenz[b,f]azepine-5-carboxamide, and its structural formula is: chemical-structure Oxcarbazepine is a white to faintly orange crystalline powder.
Oxcarbazepine is an antiepileptic drug used for the treatment of partial-onset seizures in adults and pediatric patients. It is available in film-coated tablets for oral administration. The chemical name of oxcarbazepine is 10,11-Dihydro-10-oxo-5H-dibenz[b,f]azepine-5-carboxamide 2.
From the Research
Definition and Mechanism of Oxcarbazepine
- Oxcarbazepine is a 10-keto analogue of carbamazepine with anticonvulsant activity 3.
- It undergoes reductive metabolism at its keto moiety to form 10-hydroxy-10,11-dihydro-10-oxo-5H-dibenz[b,f]azepine-5-carboxamide (MHD), which is glucuronidated and excreted in the urine, with minimal involvement of the hepatic cytochrome P450-dependent enzymes 4.
Clinical Use and Efficacy
- Oxcarbazepine is indicated for treating partial-onset with or without secondary generalized tonic-clonic seizures, in both adults and children aged over 6 years, as monotherapy or adjuvant therapy 5.
- It has been shown to be effective in partial and secondarily generalized seizures in children and adults, with efficacy similar to carbamazepine, valproic acid, or phenytoin, but with fewer adverse events and better tolerability 6, 3, 7.
- The recommended titration scheme for adults is to start with 150 mg/day at night and increase by 150 mg/day every second day until a target dose of 900-1200 mg/day is reached 4, 6.
Safety and Tolerability
- The most commonly reported adverse events associated with oxcarbazepine are somnolence, dizziness, headache, nausea, and vomiting 3.
- Asymptomatic hyponatremia has been observed in patients undergoing treatment with oxcarbazepine, most frequently in patients with diseases or medications predisposing to hyponatremia 6, 7, 5.
- Oxcarbazepine has a lower propensity for interactions than older antiepileptic drugs, but it can interact with some drugs, such as phenytoin and oral contraceptives 3, 5.