OxcarbazepiOxcarbazepinene
Indications
Oxcarbazepine is indicated for:
Adults: Monotherapy or adjunctive therapy in the treatment of partial seizures
Pediatrics:
- Monotherapy in the treatment of partial seizures in children 4-16 years
- Adjunctive therapy in the treatment of partial seizures in children 2–16 years
Pharmacology
The pharmacological activity of Oxcarbazepine is primarily exerted through the metabolite derivative (the monohydroxy derivative, MHD) of Oxcarbazepine. The mechanism of action of Oxcarbazepine and MHD is thought to be mainly based on blockade of voltage-sensitive sodium channels, thus resulting in stabilization of hyper excited neural membranes, inhibition of repetitive neuronal firing and diminishment of propagation of synaptic impulses.
Dosage And Administration
Adults: initiate with a dose of 600 mg/day, given twice-a-day
- Adjunctive Therapy: Maximum increment of 600 mg/day at approximately weekly intervals. The recommended daily dose is 1200 mg/day
- Conversion to Monotherapy: withdrawal concomitant over 3 to 6 weeks;reach maximum dose of Oxcarbazepine in 2 to 4 weeks with increments of 600 mg/day at weekly intervals to a recommended daily dose of 2400 mg/day
- Initiation of Monotherapy: Increments of 300 mg/day every third day to a dose of 1200 mg/day.
- Creatinine Clearance <30 mL/min: Initiate at one half the usual starting dose and increase slowly
Pediatrics: initiation with 8 to 10 mg/kg/day, given twice-a-day. For patients aged 2 to <4 years and under 20 kg, a starting dose of 16 to 20 mg/kg/day may be considered. Recommended daily dose is dependent upon patient weight.
- Adjunctive Patients (Aged 2–16 Years): For patients aged 4 to 16 years, target maintenance dose should be achieved over 2 weeks. For patients aged 2 to <4 years, maximum maintenance dose should be achieved over 2 to 4 weeks and should not to exceed 60 mg/kg/day
- Conversion to Monotherapy for Patients (Aged 4-16 Years): Maximum increment of 10 mg/kg/day at weekly intervals, concomitant antiepileptic drugs can be completely withdrawn over 3 to 6 weeks
- Initiation of Monotherapy for Patients (Aged 4–16 Years): Increments of 5 mg/kg/day every third day
Interaction
Oxcarbazepine and its metabolite inhibit the enzyme CYP2C19 and therefore, interactions could arise when co-administering high doses of Oxazep with medicinal products that are metabolised by CYP2C19 (e.g. phenobarbital, phenytoin). Concurrent use of Oxazep with hormonal contraceptives may render few contraceptives ineffective (e.g. Ethinylestradiol and Levonorgestrel preparations). Co-administration of Oxazep lowers AUC of felodipine and Verapamil decreases bioavailability of MHD.
Contraindications
It is contraindicated to patients with hypersensitivity to the active substance or to any of the excipients.
Side Effects
The most commonly reported adverse reactions are somnolence, headache, dizziness, diplopia, nausea; vomiting and fatigue. Very rarely clinically significant hyponatraemia can develop during Oxazep use. Class I (immediate) hypersensitivity reactions including rash, pruritus, urticaria, angioedema and reports of anaphylaxis have been received.
Pregnancy And Lactation
Pregnancy: Data on a limited number of pregnancies indicate that Oxcarbazepine may cause serious birth defects (e.g. cleft palate) when administered during pregnancy. In the newborn child. Bleeding disorders in the newborn caused by antiepileptic agents have been reported. As a precaution, vitamin K1 should be administered as a preventive measure in the last few weeks of pregnancy and to the newborn. Oxcarbazepine and its active metabolite (MHD) cross the placenta. Neonatal and maternal plasma MHD concentrations were similar in one case.
Lactation: Oxcarbazepine and its active metabolite (MHD) are excreted in human breast milk. Therefore, Oxazep should not be used during breast-feeding.
Precautions And Warnings
Alcohol: Caution should be exercised if alcohol is taken in combination with Oxazep therapy, due to a possible additive sedative effect.
Withdrawal: As with all antiepileptic medicinal products, Oxazep should be withdrawn gradually to minimise the potential of increased seizure frequency.
Therapeutic Class
Adjunct anti-epileptic drugs